Mate choice is important for successful reproduction, and consequently species have evolved various ways to choose potential high-quality mates. Anuran mate choice and underlying processes have been the subject of several recent investigations, however we are far from a complete understanding of mate choice in this system. In the present study, when given a simultaneous choice between a male and a female of identical size, males did not discriminate between the sexes, and attempted to clasp a male or a female with equal frequency. Test males only released the stimulus toad when a release call was emitted by the stimulus male. When two males with distinct size differences were provided with a male, the male chose the larger one. Moreover, males discriminated between gravid females that differed in body size, choosing larger gravid females over smaller ones. These results suggest that male Bufo gargarizans can discriminate between the sexes, probably based on male release calls, and prefer to mate with larger individual using visual cues.