Nursing staff are exposed to long-term high workloads, and effort-reward imbalance (ERI) may affect their professional experience and psychological well-being. However, the mechanisms underlying its effects on ERI, including compassion satisfaction and compassion fatigue, remain unclear. Therefore, this study used a convenience sampling method to recruit 916 clinical nurses from three general hospitals in Shanxi Province, China. Unconditional quantile regression revealed that ERI was significantly associated with compassion satisfaction only at the P₃₃–P₄₈、P₄–P₇ and P₅₉–P₆₂, whereas its association with compassion fatigue was significant across the P₅–P₅₈ and P₇₆–P₉₇ quantiles, indicating distributional heterogeneity. Multiple mediation analysis demonstrated that ERI exerted indirect effects on compassion satisfaction and compassion fatigue through rumination and psychological resilience. These findings suggest that greater attention should be paid to ERI levels among nursing staff, and differentiated interventions should be implemented for different risk groups to improve their professional experience and psychological well-being.