Belief in a just world mediates the relationship between institutional trust and life satisfaction among the elderly in China

• The retirees tended to report positive trust, high BJW, and high life satisfaction.
• Institutional trust was positively associated with life satisfaction.
• Belief in a just world mediates the link between institutional trust and life satisfaction.

This study investigated the relationship between institutional trust and life satisfaction, and the mediating role of belief in a just world (BJW) among the elderly. The General Belief in a Just World Scale (GBJW) and Satisfaction with Life Scale (SWLS) were employed. A self-developed Institutional Trust questionnaire was used to measure participant’ levels of trust in eight institutions. The aggregate score for all eight items represented the level of institutional trust. The questionnaires were completed by 19,352 retirees ranging in age from 50 to 99 (M = 69.7, SD = 8.0). The results showed the following: (1) overall, the retirees tended to report high institutional trust and high life satisfaction; (2) institutional trust was positively associated with life satisfaction; and (3) more importantly, the relationships between institutional trust and life satisfaction were partially mediated by GBJW. This finding provides a new insight into the psychological mechanisms by which institutional trust relates to individual happiness. The theoretical and practical implications of these findings, as well as the study’s limitations, are discussed.