According to a statement from HI, the decision was taken under rule 4(f) of Hockey India Rules and Regulations during its 15th Executive Board meeting held here.
The 63-year-old Koshy was elected as the vice-president of HI on August 5, 2010. But she was later appointed as the interim president of the national body on November, 2010 after octogenarian Vidya Stokes resigned from the post.
A former state-level player and centre-forward, Koshy has been associated with hockey administration since 1994 and is Hockey Kerala's senior vice-president.
Koshy said it was an honour to be confirmed as the president of HI.
"The sport is poised at an exciting stage in India and it is a privilege to be working with colleagues who are committed to the cause of hockey," she said.
Also during the meeting, Gayatri Shetty, treasurer of Hockey Karnataka, was named as vice-president of HI under rule 4 (f) of Hockey India Rules and Regulations due to the vacancy created by Koshy's elevation.