PurposeDrawing on the Ability–Motivation–Opportunity (AMO) theory, this study aims to test the effect of green human resource management (G-HRM) on green organizational citizenship behavior (G-OCB) taking into consideration green culture as the mediator and green values as the moderator.Design/methodology/approachValid data from 240 entities collected in Taiwan were analyzed to test the five hypotheses. The valid data were analyzed using confirmatory factor model, correlation analysis, structural equation modeling and bootstrapping analysis.FindingsThe results for all relationships show significant associations. G-HRM is significantly associated with G-OCB and green culture, while green culture is significantly related to G-OCB. The mediating effect of green culture on the G-HRM-G-OCB relationship is significant. The moderating effect of green values on the green culture–G-OCB relationship is significant.Originality/valueThe originality of this study lies in being one of the first study in an advanced emerging economy utilizing the AMO theory.