Heslop took third place in the men’s platform event in the Spanish capital.
He was only beaten by Mexican divers Randal Willars and Kevin Berlin.
Heslop, representing Great Britain, improved through each round on his way to a podium finish.
The Plymouth youngster was sixth in the preliminary rounds with 355.20 points.
He then finished second in his semi-final with 382.60points, before scoring 391.15 in the final.
Heslop was consist all the way through the final and finished with a high-scoring 74.25 points for his last dive.
His Plymouth Diving team-mate Kayleigh Sinclair just missed out on reaching the final of the women’s three-metre event.
Sinclair finished fourth in her semi-final, with the top three progressing. She scored 242.85 points, which was 20 more than she had scored in the preliminary round where she was 10th overall.
Fellow Plymouth diver Madeline Coquoz, representing Switzerland, finished ninth in the prelims, but could not repeat her form in the semi-finals and came sixth.