Objective To develop a military cross-cultural symptom scale (MCCSS) and evaluate its reliability and validity. Methods The dimensions and items of the scale were determined through literature analysis, questionnaire surveys, group discussions, expert consultations, and pre-experiments. Cluster sampling was employed to collect data from the participants to examine the psychometric properties of the scale. Results The MCCSS comprised 38 items across 9 factors: depression, anxiety, somatic symptoms, misanthropic tendency, sleep problems, compulsions, psychotic symptoms, stress trauma, and defensiveness. Item analysis revealed that the 37 items (except 1 forced-choice item) exhibited correlations from 0.538 to 0.875 with the total scale score (all P＜0.01), with critical ratios ranging from 5.190 to 28.149, indicating good discriminative power. The Cronbach’s α coefficients for the total scale and subscales ranged from 0.825 to 0.972, and the Spearman-Brown split-half reliability coefficients ranged from 0.747 to 0.955. The results of confirmatory factor analysis showed that χ²/df＝3.419, standardized root mean square residual＝0.033, root mean square error of approximation＝0.073, normed fit index＝0.868, incremental fit index＝ 0.903, Tucker-Lewis index＝0.887, comparative fit index＝0.902, and the scale’s first-order 9-factor model fit well. The loads of each item on the factor to which it belonged ranged from 0.597 to 0.954 (all P＜0.01). The correlation coefficients between the scale and the scale for criterion-related validity ranged from 0.392 to 0.773 (all P＜0.01), and the correlation coefficients between the scale and the scale for convergent validity ranged from 0.257 to 0.519 (all P＜0.01). Conclusion The MCCSS in this study has good reliability and validity and can be used as a mental health testing and screening tool for military personnel.