Objective: To further establish the psychometric properties of the Parent Supervision Attributes Profile Questionnaire (PSAPQ), a questionnaire measure of parent supervision that is relevant to understanding risk of unintentional injury among children 2 through 5 years of age. Methods: To assess test-retest reliability, parents completed the PSAPQ twice, with a one month interval. Internal consistency estimates for the PSAPQ were also computed. Confirmatory factor analyses were applied to the data to assess the four factor structure of the instrument by assessing the convergent and divergent validity of the subscales and their respective items. Results: Test-retest reliability and internal consistency scores were good, exceeding 0.70 for all subscales. Factor analyses confirmed the hypothesized model–namely that the 29 item questionnaire comprised four unique factors: protectiveness, supervision beliefs, risk tolerance, and fate influences on child safety. Conclusions: Previous tests comparing the PSAPQ with indices of actual supervision and children’s injury history scores revealed good criterion validity. The present assessment of the PSAPQ revealed good reliability (test-retest reliability, internal consistency) and established the convergent and divergent validity of the four factors. Thus, the PSAPQ has proven to have strong psychometric properties, making it a unique and useful measure for researchers interested in studying links between supervision and young children’s risks of unintentional injury.