Deteriorating environmental conditions and frequent environmental incidents have urged corporations' execution on corporate environmental responsibility (CER). For maintaining a positive CER, buyers have considered the performance of their suppliers' CER when the buyers plan to sign or renew a contract with their suppliers. However, it is still under-examined how the mechanism works between supplier CER and buyer repurchase intention (BRPI). This study explores the mediating effects of relationship quality between supplier CER and BRPI. Based on 209 samples of Chinese buyers, the results show that supplier CER has a significant direct effect on buyer satisfaction and trust (the two components of relationship quality), and the relationship quality mediates the effects of supplier CER on the BRPI. This study provides insights into relationship marketing through crosslink CER with the relationship quality theory to explain the mechanism of how supplier CER benefits buyer purchase intention.