We examined the hypothesis that pain increases negative person perception of irrelevant others in both medical and laboratory settings in three studies. Patients perceived a nurse as more negative if the injection they received from the nurse produced more pain (Pilot Study). Patients rated neutral faces as more negative after receiving an injection than before it (Study 1). Participants who performed a painful cold pressor task rated neutral faces as more negative than a control group, but this effect only appeared for those with low perceived social support (Study 2). These findings suggest that one's experience of physical pain may be metaphorically transferred to perceptions of completely irrelevant others, inducing negative interpersonal perception. And perceived social support can ameliorate the negative effect.