According to The (Jamshedpur, Jharkhand) Avenue Mail newspaper, Sen joined Tata Steel in 1981 as a graduate trainee and worked his way up the ranks. In 2008, he was named vice president for TQM and flat products. He was promoted as president in 2013. 

In his retirement, Sen, who was named the 2018 AIST Steelmaker of the Year, will continue as a board member of Tata Bluescope, Tinplate, Nat Steel, Bhusan Plant and Jamshedpur Continuous Annealing & Processing Company Pvt. Ltd. 

His position as president at Tata Steel will be retired as well.