Railways' contingent makes one-third of the entire Indian Olympic contingent, the biggest among all sports organisations in the country.
Besides hockey, sports persons from Railways will compete in archery, atheletics, boxing, shooting wrestling, swimming and weightlifting.
Almost the entire Indian women hockey team is made up of players from Railways, as is the weightlifting team, a statement said.
From 12 railway sports persons of the total 81 Indian athletes in the 2012 London Olympics to more than 35 athletes in the Rio Olympics in a 121-member Indian contingent is a testimony to the effort that Railways has put in promoting and supporting sports in India, it said.