Perfectionism, especially the evaluative concerns domain, correlates positively with mental health distress. The Frost Multidimensional Perfectionism Scale (F-MPS) is one of the most widely used measures of perfectionism, but has not been validated in children or as a measure of parent-report of child perfectionism. The present study aimed to validate the reliability and concurrent, convergent, and factor analytic validity of the F-MPS as a measure for young children. The F-MPS was administered to a sample of 114 children ages 8–12, and their parent. Results suggest that the F-MPS is valid for parent, but not child, report of child perfectionism. The lack of support for the child report may be due to developmental limitations of children understanding and reporting of their own perfectionism traits. In contrast, parent-report using the brief version of the F-MPS appears to be an economical and valid measure of perfectionism in young children. Improved measures of perfectionism in youth would aid in early intervention to buffer the negative mental health effects of the maladaptive aspects of perfectionism.