<p>Unethical pro-organizational behavior (UPB) has produced inconsistent effects on employee workplace well-being. Past studies often treat UPB as a unidimensional construct and, hence fail to consider its heterogeneous motivational characteristics. Based on self-determination theory, we examine the separate effects of two distinct UPB subtypes—IUPB and CUPB—on workplace well-being, with basic psychological needs satisfaction playing a mediating role. Data were collected from Chinese salespeople at three time points and 207 valid participants. The hypotheses were tested by confirmatory factor analysis, hierarchical regression, and bootstrap mediation analysis. Results show that CUPB negatively predicts workplace well-being, while IUPB does not have such an effect. The negative effect of CUPB on well-being is fully mediated by basic psychological needs satisfaction, with different roles played by the basic psychological needs satisfaction of autonomy, competence, and relatedness. This study adds to the literature by assessing the multidimensional structure of UPB and shedding light on the motivational driving forces that underlie its opposite effects on employee well-being. The findings also provide guidance to organizations in terms of reducing compelled unethical behavior and enhancing employee well-being through protecting basic psychological needs and moral workplace climates.</p>