Although we have learned a great deal about rapid estrogen receptor signaling mechanisms in the past decade, we know far less about rapid androgen receptor signaling mechanisms. In fact, there are very few studies showing that the activation of androgen receptors can rapidly affect behavior through non-genomic mechanisms. We therefore conducted a series of experiments to determine if testosterone (T) rapidly affects sexual behaviors in male goldfish through such androgenic mechanisms. Initial studies showed that injections of Fadrozole, which block T’s conversion to estradiol and concomitantly elevate endogenous T levels, stimulate courtship responses within 1 hour in tests that emphasized pheromone signaling to elicit courtship. We therefore hypothesized that androgens may rapidly facilitate the processing of female sex pheromones. Indeed, when the post-ovulatory pheromone prostaglandin F2alpha (PGF2alpha) was infused into male tanks in tests done late in the breeding season, T rapidly (within 1 hr) stimulated approach responses towards the source of the pheromone. In a subsequent test done early in the breeding season, fish injected with T, Fadrozole, or T and Fadrozole all tended to increase activity in the presence of PGF2alpha relative to vehicle injected controls (p=0.054 for the comparison between the T+FAD group and the vehicle injected control group). Together, these studies provide preliminary evidence that T, working through androgen receptors, rapidly stimulates behavioral responses to sex pheromones in male goldfish.