Numerous empirical studies have extensively explored the impact of respect for supervisors on employees’ sense of belonging and trust, confirming its positive effects on these outcomes. Nevertheless, scarce attention has been given to what factors connected the respect for supervisors and employees’ sense of belonging and trust. To fill this gap, and under the perspective of leader-member exchange (LMX) theory, this study proposes organizational fairness as the mediating factor that connects the effects that respect for leaders promotes employees’ development of a sense of belonging and trust. Data collected from 277 employees of small to medium technology enterprises were analyzed using Partial Least Squares-Structural Equation Modeling (PLS-SEM), revealing several key findings. Respect for supervisors positively affects both belonging and trust. Additionally, the mediating role of various types of justice was confirmed. Procedural justice mediated the relationship between respect and belonging, as well as between respect and trust. Distributive justice demonstrated similar mediation effects between respect and both belonging and trust. Interpersonal and informational justice also mediated these relationships. These findings underscore the critical role of justice perceptions in fostering employees’ feelings of belonging and trust within the workplace. This study provides theoretical implications for organizational fairness and LMX theory, as well as practical implications for leadership and organizational management.