Based on referent cognition theory (Folger 1986), the present study investigated the effects of perceived skill underutilization on distributive justice or equity, and the effect of perceived supervisor support on this relationship. Data were collected during the summer of 1989 among salaried blue-collar employees of a unionized manufacturing plant in the southeastern United States. Multiple regression analyses were used to examine the relationships. The results supported the hypothesized negative relationship between perceived skill underutilization and distributive justice or equity. Thus, the greater the perceived skill underutilization, the less the distributive justice or equity. Although the interaction between skill underutilization and supervisor support was not significant, there was a main effect of supervisor support on distributive justice. The greater the supervisor support, the greater the distributive justice or equity. The implications of supervisor support for the distributive-procedural justice interrelationship and the role of the union in workplace justice are discussed.