Development of a mixed phase MoS2 (1T/2H)-CdS supported on rGO photo-electrochemical catalyst for hydrogen production by splitting of water using visible light, has been reported. This catalyst showed a better efficiency compared to catalysts where either MoS2 was incorporated with CdS or MoS2 alone was supported on rGO. All the catalysts were photoactive under negative biasing. A detailed characterization of catalysts was performed using FTIR, XRD, DRS, HRSEM, HRTEM, SAED, XPS, and EIS etc. Higher activity of MoS2-CdS-rGO correlated with the formation of a mixed phase of MoS2, as well as a heterojunction at the interfaces of MoS2-CdS-rGO. Formation of the heterojunction and the presence of mixed phases of MoS2 have resulted into a better charge separation, a higher charge density and low resistance for charge transfer. These factors have attributed a higher efficiency of the catalyst. The probable mechanism of charge transfer is also discussed. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.