PurposeThe purpose of this paper is to verify the mediating role of commitment between market-oriented organizational culture and international market performance, and to discuss the moderator effect of national institutional environment on this mediating role.Design/methodology/approachThe research design follows a mixed methodology, combining qualitative and quantitative data collection and analysis. In the first phase, research hypotheses are proposed based on a literature analysis. In the second phase, sample data are collected through interviews and questionnaires sent to domestic contractors in China and South Korea, and a validity analysis of the results is carried out. Correlation and regression analyses are then performed on the valid data to verify hypotheses to prove the existence and influence of mediating effects. Hayes PROCESS Macro is used on the regression results to test the mediating effect of commitment on international project performance and the moderation effect of institutional environment.FindingsThe results reveal that the commitment between partners has a mediating effect on the relationship between market culture and international project performance; however, no hierarchy culture is revealed. The mediating effect of commitment is regulated by the institutional environment.Research limitations/implicationsAlthough the reliability and validity of the questionnaire data in this study are in line with research standards, a larger sample size would improve the reliability of the results. Further, the interviewed samples are mainly from China and South Korea; large representative samples from additional countries, such as Japan, should be considered to gain a fuller understanding and more comprehensive results.Originality/valueBy emphasizing the differences between the two institutional environments of developing and developed countries in East Asia, a theoretical and empirical basis is provided. International construction enterprises in other countries can apply the findings to improve their international market performance in different institutional environments. The findings also provide an empirical reference that international construction enterprises in China and South Korea may use to adjust their organizational cultures and commitments to improve market performance.