Predominantly appears in Tamil films and also has appeared in Hindi and Telugu films.

She made her debut in a national competition by competing in the 52 kg category at the 2009 Asian Indoor Games as a kickboxer.

After competing 2009 Asian Indoor Games and then participating in the Super Fight League, she played a leading role in Sudha Kongara Prasad's Tamil film Irudhi Suttru alongside R. Madhavan.

She won Special Mention at the 63rd National Film Awards for her performance in Irudhi Suttru.

Ritika Singh trained as a kickboxer and as a mixed martial artist from her childhood, under the guidance of her father.

She subsequently appeared in the inaugural season of the Super Fight League and competed as a mixed martial artist.

In 2013, Singh was spotted by director Sudha Kongara Prasad in an advert for the Super Fight League and was later auditioned to play a leading role in her bilingual film, Saala Khadoos (2016).

For the film Irudhi Suttru, Singh phonetically learned her part in Tamil by writing down the dialogues in Hindi.

For her performance in Irudhi Suttru, Ritika won the a Special Mention at the 63rd National Film Awards, and became the first actress, who did not dub for her role, to be recognised at the National Awards.

Ritika Singh later appeared in Manikandan's Aandavan Kattalai, which was released in September 2016.

As of September 2016, Singh is working on P. Vasu's Shivalinga and Guru, the Telugu remake of Irudhi Suttru.