The present study examined sex differences in awareness of smiling behavior during a job interview, along with intended outcomes of false smiling. Male and female participants were assigned to the interviewee role of a mock job interview and were videotaped. Results indicate that women were more self-aware of false, but not genuine, smiling. In addition, women reported using false smiles to mask negative emotion and to appear enthusiastic more than did men. Naïve judges rated women who smiled in an attempt to mask negative emotion more harshly than men who smiled for this reason. Implications of these findings for the understanding of sex differences in smiling are discussed.