In many species of anurans, tadpoles adjust their behavior in the presence of fish or fish cues, in many cases reducing their activity. Tadpoles may also adjust their activity or behavior in response to group size. We examined the effects of predator cues (bluegill sunfish, Lepomis macrochirus) and group size on the behavior of Wood Frog (Rana sylvatica) tadpoles in a factorial laboratory experiment. Wood Frog tadpoles were less active and used the vegetated side of the experimental aquaria more in the presence of fish. Group size alone had no effect on the behavior of the Wood Frog tadpoles in our experiments. Our experiment shows that cues from fish predators have a greater influence on the behavior of Wood Frog tadpoles than does group size, at least in the range of group sizes used in this experiment.