CdS and MoS2 are both promising photocatalytic materials for hydrogen production and lots of MoS2/CdS composites have been investigated. However, most of the previous work focused on relatively stable hexagonal CdS; researches on cubic CdS are still rare mainly due to its unstability. Then in this paper, a ternary composite MoS2/CN/CdS composed of cubic CdS, MoS2 and graphitic carbon nitride (g-C3N4, abbreviated as CN) was prepared by simple in situ precipitation of cubic CdS on MoS2/CN at room temperature. Based on a series of characterizations, the photocatalytic hydrogen production performance of MoS2/CN/CdS was studied. The results showed that when the amount of MoS2/CN was 10 wt.%, the activity reached 1253.2 [Formula: see text]mol h[Formula: see text], about 110 times that of pure CdS. Especially, its stability was investigated in detail by cyclic hydrogen production tests, which indicated that although the activity decreased after the first cycle, it was stable in the following three cycles mainly due to the existence of CN. Namely, a relatively stable and high performance cubic CdS-based ternary composite was achieved. This research can provide some new insights into the design of cubic CdS-based photocatalysts.