Sharing attention with interactive social partners, referred to as social attention, is fundamental to our efficient social interactions and adaptive functioning, since it enables us to learn about the other person’s inner state and where the important events are in the environment. In recent years, researchers have systematically investigated the specific cognitive and neural mechanisms of social attention using a combination of psychophysical paradigms (e.g., adapted central cueing paradigm), neuroimaging techniques (e.g., ERP, fMRI, MEG) as well as neuropsychological methods (e.g., brain-damaged patients). Some studies have demonstrated that social cues (e.g., eye gaze, head orientation and biological motion walking direction) can trigger reflexive attentional orienting effect, which is unique and qualitatively distinct from the attentional effect induced by nonsocial cues (e.g., arrow) in terms of both behavioral responses and neural activities. However, other studies have found that social and nonsocial attention share common neural substrates, and there is still controversy concerning the specificity of social attention. Combined with previous evidence, the major distinction between social and nonsocial attention is plausible that social attention might be mediated by an innate and genetically determined module, while nonsocial attention may occur as a result of long-term experience (overlearning). Future research, exploring the genetic origins of social and nonsocial attention, may help to provide evidence for the existence of “social attention detector” and highlight the role of social attention in the early diagnosis and clinical intervention of autism.