The intimate contact of co-catalyst and host photocatalyst benefits the separation and transfer of carriers in time, hindering the recombination of e(-) and h(+) during the photocatalytic process. Herein, a facile one-pot solvothermal methodology was applied to fabricate NiS clusters-modified Mn0.3Cd0.7S p-n heterojunction photocatalyst. Compared with [email protected] synthesized by the two-step approach, the symbiosis of NiS and Mn0.3Cd0.7S during one-pot synthesis induced the highly dispersed NiS clusters on the surface of Mn0.3Cd0.7S nanorods and the stronger intimate contact between NiS and Mn0.3Cd0.7S, giving rise to better H-2 production of 65.81 mmol g(-1) h(-1). The apparent quantum yield reached 20.19%. The study presented a feasible route for the synthesis of cheap and efficient p-n heterostructure photocatalysts.