- He played a key role in major terrorism-related cases in the country. He helped in convicting Ravinder Singh for the Kalyan bomb blast in 1991. He went on to become the public prosecutor for the Mumbai serial blasts case in 1993.
- Ujjwal Nikam's legal career also saw him take up several high-profile assignments such as the murder case of Bollywood producer and T series founder Gulshan Kumar in 1997.
- He was also the prosecutor in the murder case of Pramod Mahajan, who was shot dead by his brother Pravin in April 2006 following a dispute.
- He was the public prosecutor in the trial of Ajmal Kasab, the only terrorist caught in the 26/11 Mumbai terror attack. He successfully argued for Kasab's death penalty.
- He was provided with Z-plus security after 2009 when he took over as prosecutor in the 26/11 case. He was awarded the Padma Shri in 2016. The BJP had fielded Mr Nikam as its Lok Sabha candidate from the Mumbai North Central constituency. He lost the seat to Congress candidate Gaikwad Varsha Eknath.
