The Midlife Women's Symptom Index (MSI) was designed to measure menopausal symptoms specifically in a multiethnic sample of midlife women. This study involved a psychometric property test to evaluate MSI among 512 multiethnic groups of midlife women (White, Hispanic, African American, and Asian American). Across the ethnic groups, the MSI had an adequate internal consistency in all subdomains except psychosomatic symptoms. The item-total correlation coefficients of lost weight and nosebleeds were lower than .20 among all ethnic groups. The discriminant validity was confirmed among all ethnic groups except Asian Americans. Overall, the MSI may work better for Whites compared with other ethnic groups. Additional studies with diverse groups of multiethnic midlife women are needed, however, to confirm the psychometric properties of the MSI because the samples tended to be a select group.