The present experiment was conducted to investigate how prior information affects subsequent person perception and when perceivers can control such an effect. One of three types of trait related words (i.e., hostility-related, friendliness-related, and neutral words) was subliminally or supraliminally presented to subjects, and subsequently, subjects rated the impression of four targets: a hostile person, a friendly person, a neutral person and themselves. Although results did not show that supraliminally presented words affected targets' impressions, they showed that the impressions sometimes varied with the valence of subliminally presented words regardless of targets' valence. The mechanism and controllability of priming effects in person perception were discussed.