Attention is captured more strongly by emotional pictures than by neutral pictures. This allocation of attention to emotional pictures is commonly indexed by the late positive potential (LPP). This event-related potential (ERP) is larger for negative and positive pictures than for neutral pictures. However, findings are mixed in regards to valence effects, that is, whether the LPP is larger for negative pictures than for positive pictures (negativity bias) or vice versa (positivity bias). Additionally, previous ERP studies have not explicitly considered a moderating effect of gender. In the present study, positive, negative, and neutral pictures were shown at fixation but were always task-irrelevant. Results showed that LPP amplitudes for the positive and negative distracters were moderated by gender. Men showed a positivity bias on the LPP (i.e., larger amplitudes for positive pictures than for negative pictures). Women did not show a clear valence bias on the LPP, but they showed a negativity bias on picture ratings. These gender differences for the LPP did not habituate, as they were obtained even for pictures that were repeated 20 times. Because previous studies with other measures suggest a positivity bias for men and a negativity bias for women, the present findings extend these studies suggesting that attention allocation for emotional pictures of different valence is similarly moderated by gender.