Hippopus porcellanus is a rare and heavily exploited giant clam species with limited distribution range in the Indo-West Pacific Region. Overharvesting has resulted in the localized extinction of H. porcellanus in the Philippines, but its populations appeared to have recovered in Tubbataha Reefs Natural Park (TRNP) after more than 20 years of protection. As one of the least studied giant clam species, the shell dimension-live weight relationships were determined. In addition, the growth parameters of H. porcellanus in TRNP were monitored with the mark–recapture method. All three shell dimensions of H. porcellanus were good estimators of live weight. The von Bertallanfy growth parameters K (0.29) and L (29.24 cm) were determined on the basis of 80 marked individuals recaptured twice within 2.5 years. Nearly 90% of marked clams survived at the end of the study. Studies on aspects of biology of other giant clams species at the park is suggested.