The Iranian team defeated Thailand 3-1 (25–14, 25–18, 15–25, 25–14) in the competition’s semi-final.
Iran will play South Korea in the final match on Saturday.
Thailand and Iraq will play in the third-place match.
The 2018 Asian Men's U-20 Volleyball Championship kicked off on July 21 and will conclude on July 28.
Iran and South Korea also qualified for the 2019 FIVB Volleyball Men's U-21 World Championship as Asian representatives.