The prevalence of autism continues to steadily rise over time. As of yet, no clear cause or cure has been identified. Nevertheless, behavioral and pharmacological treatments have been developed to lessen the deficits characteristic of autism. These treatments yield the best results when implemented early in a child’s life. Early identification of autism lends itself to early intervention. Many assessments have been developed for this purpose. Most measurements have focused on specific symptoms of autism. More recently, this effort has expanded to include assessments based on temperament and personality. The present study used the M5-PS Questionnaire based on the Five-Factor Model to compare personality differences in children with autism and typically developing children age 3 to 5. Typically developing children achieved significantly higher scores on Extraversion, Agreeableness, Conscientiousness, and Openness to Experience. The groups did not differ on Neuroticism.