Born in Noamundi, Jharkhand, Mondal began playing football from a young age in his district. He was spotted by Tata Football Academy coach, Ranjan Chowdhury, at the age of sixteen who invited Mondal to join the academy. Mondol graduated from the Tata Football Academy in 1998. After graduating from the academy, Mondal signed with National Football League side, JCT Mills Phagwara. He stayed at the club for two seasons before joining Kolkata side, East Bengal. It was at East Bengal that Mondal began to impress and even earn himself caps for India. On 30 December 2002, after impressing the All India Football Federation and national team head coach, Stephen Constantine, with his performances in the Asian Games and the ASEAN Club Championship for East Bengal, Mondal was named the AIFF Player of the Year. On winning the award, AIFF president at the time, Priya Ranjan Dasmunsi, said that Mondal "infused a new confidence in the deep defense". Overall, while with East Bengal, Mondal won the National Football League title three times, two Durand Cup's, and four Calcutta Football League titles. While at East Bengal, Mondal was part of a strong backline with Surkumar Singh and Mahesh Gawli.