Parents' rules regarding child television, DVD, video game, and computer use (screen time) have been associated with lower screen use in children. This study aimed to identify modifiable correlates of this behavior by examining social-cognitive predictors of parents' restriction of child screen time. Low-income parents ("N" = 147) of preschool-aged children (2-6 years) completed self-administered questionnaires examining parent and child screen time, parent restriction of screen time, self-efficacy to restrict screen time, and beliefs about screen time. Structural equation modeling results indicated that greater self-efficacy to restrict screen time (ß = 0.29, "p" = 0.016) and greater perceived importance of restricting child screen use (ß = 0.55, "p" < 0.001) were associated with greater restriction of child screen use, after controlling for parent screen time. Family-based interventions that consider broader attitudinal factors around child screen time may be necessary to engage parents in restricting screen use.