This study is part of a larger United States Geological Survey of the bees in the United States as part of a monitoring program of the flora and fauna of North America. While bees have been studied across Pennsylvania, in New York City and Baltimore, this is the first documented survey of the bees of Philadelphia. I sampled bees by netting once in July, August, and September. A total of 280 bees, representing 58 species were captured. This is the first record of several bee species for Pennsylvania, including the recently introduced Hylaeus hyalinatus Smith and Coelioxys coturnix Perez. I also document the presence of Bombus pensylvanicus Perez, a bumble bee that may be in decline. This study can be used to guide monitoring and conservation efforts.