Moni Singh achieved his initial success in 1928 when he led a 13-day long strike by the workers of Kesharam Cotton Mills at Metiaburuj in Kolkata and had their demands fulfilled. He was arrested in 1930, and on his release from jail in November 1937 he came back to Susang-Durgapur. There he organised the farmers and led a peasants’ movement to protest against Tanka system. He was one of the chief organisers and president of reception committee of the convention of Nikhil Bharat Kishan Sabha held at Netrakona in 1945.