This research examines whether a single variable–professional competence–may account for workplace psychological health either directly or else indirectly through the satisfaction of basic psychological needs (autonomy, competence, and relatedness). Our sample was composed of 499 teachers at both the elementary and secondary school levels.Structural equation modelling was used to validate the relationships between variables, and the bootstrapping resampling method allowed us to validate the proposed mediation model. The results indicate that two aspects of workplace psychological health (well-being and distress) are influenced by professional competence. The three basic psychological needs play a mediating role in this relationship.