This study attempted to develop a standardized instrument for assessment of prosocial reasoning in Chinese populations. The Prosocial Reasoning Objective Measure (PROM) was translated, and a two-stage study was conducted to evaluate the psychometric properties of the translated instrument. The content validity, cultural relevance, and reading level of the translated instrument were evaluated by an expert panel. Upon revisions according to the expert opinions, the Chinese PROM demonstrated good content validity, "good-to-very good test-retest" reliability, and internal consistency. However, only partial support to the convergent validity of the Chinese PROM was found. In the first stage of the study (n = 50), the PROM scores had high positive correlations with empathy and negative correlations with personal distress and fantasy. These results were consistent with theoretical expectations, although this is also a concern that empathy had a close-to-unity correlation with PROM score in the small sample study of stage 1. In the second stage of the study (n = 566), the relationship between PROM scores and prosocial behavior appeared to be weak. Results suggest that there were many personal, family, or social factors that were linked to prosocial behavior, and prosocial reasoning might only contribute to a small proportion of variation in prosocial behavior among adolescents. Copyright © 2012 Frank H. Y. Lai et al.