Caregiver strain is associated with caregiver and child well-being and clinical outcomes. The present study examined the psychometric properties of a revised 11-item measure of caregiver strain, the Caregiver Strain Questionnaire–Short Form 11 (CGSQ-SF11). In a sample of 962 caregivers, we found support for a three-factor model of the CGSQ-SF11, consisting of objective (e.g., financial impact), subjective internalized (e.g., sadness about the child’s problems), and subjective externalized (e.g., anger directed toward the child) strain factors. Measurement invariance was supported across multiple demographic and clinical groups, and all three subscales displayed high internal consistency. Convergent validity was also supported through positive correlations with measures of child psychopathology symptoms and psychosocial impairment. Moreover, caregiver strain was associated with number of child disorders as well as breadth of child symptoms across both internalizing and externalizing domains. Findings provide initial validation of the CGSQ-SF11 as a comprehensive yet brief measure of caregiver strain.