To further the understanding of the relations among sociocognitive abilities and social behavior, the current study examined theory of mind (ToM), social information processing (SIP), and prosocial behavior in 116 preschoolers (M age = 58.88 months) in Turkey. False belief tasks were utilized to test ToM and cartoons were used to assess SIP patterns. Prosocial behavior was measured with mother-reports and individual assessments. ToM was not related with the attribution of intent and was the only sociocognitive predictor of prosocial behavior, but just in boys. Results also pointed at sex differences in levels of sociocognitive development; girls showed greater ToM and more non-hostile attribution. Findings imply that SIP patterns might be less closely related to positive than antisocial behaviors, and understanding others’ minds might be less needed for positive acts in Turkish girls, who may learn to engage in such behavior as part of their gender role more strongly.