Variations in children's problem behaviors associated with ethnicity and other demographic variables were examined in 6–18-year-old children (N=804) residing in a multicultural environment. The Child Behavior Checklist–Teacher's Report Form was used to compare the frequency of behavior problems among clinic-referred and nonreferred children of Hawaiian, Asian, and Caucasian ethnicities. Children who were male, clinic-referred, or of Caucasian or Hawaiian ancestry experienced greater levels of behavioral problems. Explanations concerning ethnic variations in children's problem behaviors include: teacher's perceptual bias, differences in teacher threshold to report problem behaviors, and/or true variations in children's behavior.