Basidiobolomycosis is a rare fungal disease caused by Basidiobolus ranarum, which is endemic in tropical and subtropical regions of Africa, Asia, and Latin America. Gastrointestinal basidiobolomycosis poses diagnostic difficulties due to the non-specific clinical presentation and absence of predisposing factors. Eight pediatric cases of the disease have been reported recently from Iran, but none of these, or most of the other cases reported in the literature, has been proven by culture, which is the gold standard method for diagnosis. We present a case of culture-proven colonic basidiobolomycosis that occurred in a 3-year-old boy. The outcome was successful following surgical excision and antifungal therapy with posaconazole.