Abstract Objective We present the results of a cross‐cultural validation of the Mental Health Global State (MHGS) scale for adults and adolescents (<14 years old). Methods We performed two independent studies using mixed methods among 103 patients in Hebron, Occupied Palestinian Territories and 106 in Cauca, Colombia. The MHGS was analyzed psychometrically, sensitivity and specificity, ability to detect clinically meaningful change, compared to the Clinical Global Impression‐Severity scale (CGI‐S). Principal component analysis was used to reduce the number of questions after data collection. Results The scale demonstrated good internal consistency, with a Cronbach alpha score of 0.80 in both settings. Test retest reliability was high, ICC 0.70 (95% CI [0.41–0.85]) in Hebron and 0.87 (95% CI [0.76–0.93]) in Cauca; inter‐rater reliability was 0.70 (95% CI [0.42–0.85]) in Hebron and 0.76 (95% CI [0.57–0.88]) in Cauca. Psychometric properties were also good, and the tool demonstrated a sensitivity of 85% in Hebron and 100% in Cauca, with corresponding specificity of 80% and 79%, when compared to CGI‐S. Conclusions The MHGS showed promising results to assess global mental health thereby providing an additional easy to use tool in humanitarian interventions. Additional work should focus on validation in at least one more context, to adhere to best practices in transcultural validation.