Maddam Sir

• Gulki Joshi as S.H.O. Haseena Mallik aka Maddam Sir / Urmila Mahadev Mhatre – SHO of MPT; Shahjaha and Noor's daughter; Anubhav's ex-fiancée; Karishma's mentor and close friend. She always handles case with intelligence and emotions believing ending crime, not criminals. She is very kindhearted and always tries to stop Karishma Singh from taking the wrong step in rage. Her team means a lot to her. She is called MADDAM SIR by her police station members. She has a catchphrase, "Tajurba Kehta Hai Hamara" (My experience says that) when she gets an idea. (2020–present)[3]
• Yukti Kapoor as S.I. Karishma Singh aka Qayamat – SI at MPT; Anubhav's cousin sister; Pushpa's daughter-in-law; Haseena's protective close friend. She is short-tempered and believes in strict policing. She dislikes Haseena's way of solving cases but she always ends up helping Haseena in her plan. Despite their differences, they love and respect each other. She is tough on the outside but inside she cares very much for people close to her. She has a catchphrase, "Darogaji dekhe to bahut par tumsa nahi dekha" (You must have seen inspectors but not like me) when handling criminals. (2020–present)
• Sonali Pandit Naik as Counsellor cum Head Constable Pushpa Singh – The oldest member of MPT and Counselling Head; Karishma's mother-in-law. She always fights with Karishma over petty things but deep inside has immense love for her. The MPT officers are distraught about her overacting. She wants to lead and solve at least one case before her retirement. She has a catchphrase, "Hamare lalla ke toh bhaag hi phoot gaye." (2020–present)[4]
• Bhavika Sharma as Cyber Crime Specialist Constable Santosh "Santu" Sharma – A police officer in charge of cyber-crime. Surinder's daughter; Ravi's sister. She is fondly called Bulbul by her parents and brother. She often behaves childishly and does mistakes but is good at internet-related matters. She is always confused about Haseena and Karishma's way of solving the cases. Cheetah Chaturvedi has a crush on her but she considers him as a friend. She wants to achieve high before getting married but her family constantly try to change her mind. (2020–present)[5]
• Yashkant Sharma / Priyanshu Singh as Constable Cheteshwar "Cheetah" Chaturvedi – A women's psychology specialist at MPT. He has a one-sided love for Santosh. Earlier he used to be very lazy and often slept on duty but later becomes responsible. He has a catchphrase, "Uff ye masumiyat" when Santosh does any mistake. (2020–present)
• Ajay Jadhav as Billu Champat – He is a thief turned spy who loves to live in jail because he doesn't have any other place to live. However, he helps his police counterparts often in solving cases by being a spy on criminals. He has a close relationship with all MPT Officers. he has a catchphrase, "Jiske peeche pad jaaye, uske muh se nikle haay haay, I'm Billu the Spy!" (2020–present)
• Rahil Azam as DSP Anubhav Singh – A negotiation specialist in IB and DSP of Lucknow; Karishma's cousin; Haseena's ex-fiancé. He pretended to be in love with Haseena Malik for a mission, but later, actually fell in love. He was ordered to call off his marriage with Haseena. However, circumstances brought them together again. He always supported the MPT. But later, He turned villain to seek revenge and kidnapped Haseena's mother. After a scene, he is killed by Karishma Singh. (2020–2022)[6]

• Satyapal Landge as Badnaam – Tea seller of the MPT locality. He is often slapped by Karishma for making bad tea and often does mimicry of Bollywood superstars. (2020–present)
• Ashwani Rathore as Iqbal – The barber of the MPT locality. He used to tell made-up stories to Pushpa and Santosh. (2020–present)
• Pankhuri Awasthy Rode as ASI Mira – A humanoid robot police officer invented by C.A.R.D. Research Institute who was sent to MPT for a 90 days trial and to learn emotions and was working under Karishma Singh as her assistant. She used to both irritate and entertain MPT officers by mimicking them with their combined traits. She ended up shooting Haseena fatally when her system got hacked which lead Karishma to switch off her button permanently. She had become full of emotions by the end. (2021–2022)[7]
• Rajesh Dubey as DSP Mahesh Singh – He was the DSP before Anubhav and had got transferred himself to his hometown but he joined Lucknow again after Anubhav went on his mission. He is a foodie who loves Pushpa Ji's cooking and food. (2020, 2021–present)
• Umesh Bajpai as Fassruddin Nawab Sahab – Owner of the mansion where the permanent Aminabad Mahila Police Thana is situated; Raees and Zeenat's father. He has a huge crush on Head Constable Pushpa Singh, unknowing that they both have a crush on each other. (2020–present)
• Roopa Divatia / Utkarsha Naik as Noorjahan Malik – Haseena's mother (Ammi). Karishma Singh is also like a younger daughter to her. She is always worried about her daughter's wedding. (2021–present)[8]
• Nimesh Soni as:
  • Bulbul Pandey – S.H.O. of JPT; Pallavi's husband; Champak's senior and brother-in-law. He is a MPT's competitor who wants to let MPT officers down. Later he is been transferred to Mahila Police Thana temporarily and creates a rift between Haseena and Karishma. (2020–present)
  • Kartik Bajaj – The owner of a cab driving company who thought that women can't drive. (2020)
  • Balli – LPJ diet plan company's owner who fooled people. (2020)
• Salman Shaikh as Rajvir Tomar aka computer – Head Constable of JPT. He has a crush on Karishma Singh unknowing that she is married. (2021)
• Amit Kumar Sinha as Champak Chaudhary – A Constable at JPT; Pallavi's brother; Bulbul's junior and brother-in-law. He oftens interrupts and insults Bulbul. (2020-2021)
• Jignesh Modi as Chedi – A Constable at JPT. (2021)
• Gaurav Wadhwa / Jatin Arora as Reporter Sunny Chaddha – He has a crush on Santosh and tries to impress her and has a competition with Cheetah. He helps MPT Team to solve cases with his reporting skills. Whenever he is reporting the news on TV, he has a catchphrase "tazi khabron ka ek Lauta adda aapka apna Sunny Chaddha.” (2020-2021)
• Prakash Ramchandani as Secret Agent Ajay Bakshi – He is Anubhav's senior who restricted him to get engaged to Haseena. He saved Haseena's life and asked her to disguise as Urmila Mahadev Mhatre, a vada pav seller in Mumbai to catch the people who tried to murder her for the hard disk. (2021–present)
• Urmila Tiwari as:
  • Shalini – A beauty parlour owner. She is a victim of money fraud via online dating app. (2021)
  • Pratha – Jaya's daughter. She was forced to follow superstition rituals by her mother to her marriage. (2021)
  • Priyali Singh – She teaches students in many schools as Aparna Bansal under a teacher's scam. (2021)
• Lakshya Handa as Avtaar Kapoor – Karishma's boss. (2021)
• Darpan Shrivastava / Harveer Singh as Usman – The Biriyani Seller of MPT locality. (2020)

• Esha Kansara as S.I. Misri Pandey – She was a corrupt police officer who came to MPT, temporarily. She was promoted to S.I. with her uncle's help, who was an influential politician. She used to take bribes from criminals and protect them. (2020)[9][10]
• Divyangana Jain as Rani – She used the faces of Haseena Malik & Qayamat (Karishma Singh) to do illegal activities. She was arrested for being Fake Haseena Malik, but she escaped from the jail and used Qayamat's face to do crime. She was again arrested. (2020, 2021)
• Roopam Sharma as Mona – Fake S.I. Barbie Upadhyay. She was a clinical psychologist, to whom Haseena Malik used to consult. She used to add pills in Haseena Malik's coffee, causing hallucinations. She was the mastermind behind the racket but pretended to be a naive and responsible officer. (2021)
• Kavita Kaushik as IPS Chandramukhi Chautala from F.I.R. She had come to solve the case of stolen Mummy. She was impressed by the MPT team. (2022)[11][12]
• Vaishali Thakkar[13] as Head Constable Babita Sarkar – Haseena and Karishma's trainer in their training days. She came to Mahila Police Thana as a replacement for Pushpa Singh for a few days. (2020)
• Apara Jariwala as Sarita Singh – Pushpa's aunt-in-law; Karishma's grandaunt-in-law. She was against women empowerment thinking married women can't handle both family and career and boycotted Pushpa for the same. At the end, She realized her mistake after Manju's case and Karishma defended Pushpa. (2022)
• Tejal Adivarekar as Malaika – Pushpa and Karishma's household help. (2021, 2022)
• Ashish Pawar as Sajan – Urmila's (Haseena) supporter and love interest. (2022)
• Prem Vallabh as Mr. Chaturvedi – Cheeta's father. (2022)
• Anju Rajiv as Mrs. Chaturvedi – Cheeta's mother. (2022)
• Abhay Bhadoriya as Bunty (Pizza Eating). (2022)
• Ketan Singh as Badshah – A thief along with his lover Begum stole many precious things to have a lavish living with her. (Special appearance for Mahasangam episode in all Sony Sab shows).
• Tunisha Sharma as ASP Aditi Jammwal from Hero - Gayab Mode On: She was handling the case along with Maddam Sir.
• Deepak Pareek as Honourable Secretary Advocate Dakshesh Joshipura from Wagle Ki Duniya - Nayi Peedhi Naye Kissey: He came to take back the stolen gold "Kalash".
• Sayantani Ghosh as Daljeet Bagga from Tera Yaar Hoon Main: She came to take back her daughter's stolen necklace.
• Vijay Kashyap as Col. Pushpinder Batra: director of Parakram SAF from Ziddi Dil Maane Na.
• Gulfam Khan as Mrs. Batra from Ziddi Dil Maane Na.
• Karan Veer Mehra as Abhay: Koel's husband from Ziddi Dil Maane Na.
• Prathmesh Sharma as Bala: Cadet of Parakram SAF from Ziddi Dil Maane Na.
• Shaleen Malhotra as Special Agent Karan Shergill from Ziddi Dil Maane Na.
• Kaveri Priyam as Cadet Dr. Monami "Monu" Mahajan from Ziddi Dil Maane Na.
• Kunal Karan Kapoor as Cadet Siddharth "Sid" Ganju from Ziddi Dil Maane Na.
• Diljot Kaur Chhabra as Special Agent Sanjana "Sanju" Dubey from Ziddi Dil Maane Na.
• Aditya Deshmukh as Special Agent Faizuddin "Faizi" Siddiqui from Ziddi Dil Maane Na.
• Simple Kaul as Cadet Koel Roy from Ziddi Dil Maane Na.

Before its premiere, it was titled Mahila Police Thana but was later changed to Maddam Sir. In early February 2020, the main cast promoted the series in Lucknow.[14]