While many businesses seek to seize the momentum of social networking sites, the combination of technology-enabled social networks and e-commerce may offer significant opportunities for retailers. Social shopping sites emerged as the latest developments to leverage the power of social networking with online shopping. Despite enormous business interests and potentials, little is known about whether users will adopt such systems. This paper extended the Technology Acceptance Model (TAM) to understand the adoption of social shopping sites. Besides perceived ease of use and perceived usefulness as proposed in TAM, this study explores three additional constructs: an online shopper’s tendency to social comparison, social presence, and perceived enjoyment in using the website. Results suggest that perceived usefulness and perceived enjoyment both affect behavioral intention to adopt social shopping sites. Users’ tendency to social comparison and perception of social presence are also significant antecedents in the model. Directions for future research are discussed.