Mrunal left KC College before being able to graduate as she was pursuing television at the time.

Mrunal began her acting career with the television soaps Mujhse Kuchh Kehti...Yeh Khamoshiyaan (2012) and Kumkum Bhagya (2014–2016).

Thakur made her Hindi film debut with Love Sonia (2018).

In 2019, she appeared in the biographical films Super 30 and Batla House.

Thakur has since starred in commercial failures Toofaan and Dhamaka both in (2021), Jersey (2022).

Mrunal Thakur had a commercial success in the Telugu film Sita Ramam (2022).

Thakur will appear opposite Abhimanyu Dassani and Paresh Rawal in the multi-starrer comedy Aankh Micholi.

Mrunal Thakur will also be seen playing the role of a police officer alongside Aditya Roy Kapur in the Hindi remake of the 2019 Tamil film Thadam.

Mrunal Thakur also completed Maddock Films Pooja Meri Jaan alongside Huma Qureshi.