Panchaya beat 20-year-old Indian player Anupama Ramachandran 4-1 in the final in Bucharest, Romania on Tuesday.
Prawit, as the president of the National Olympic Committee, congratulated her for becoming the first female Thai snooker player to win the World Under-21 Championship, a Defence Ministry spokesman said on Friday.
Prawit also thanked the Billiard Sports Association of Thailand for supporting players on the global stage and making the country proud.
The caretaker PM said the government would encourage Thai youths to play more sport and support national athletes by using sports science in their preparations for international competition.