The first round would be featured by 36 clubs which were the winners of the qualification round and the new entries including 16 clubs from 2019 Thai League 1, 1 club from 2019 Thai League 2, 2 clubs from 2019 Thai League 3, 4 clubs from 2019 Thai League 4, and 5 clubs from 2019 Thailand Amateur League. This round had drawn on 19 April 2019.
