Using yeasts as biological templates, flower-like g-C3N4/Bi2MoO6 microspheres were prepared via hydrothermal-template sacrifices method. The crystal phase, microstructure, light absorption and specific surface area of the as-prepared sample was characterized with various techniques including XRD, SEM, TEM, FT-IR, DRS, photocurrent response and nitrogen adsorption-desorption. We also examined the visible-light driven photocatalytic performance of g-C3N4/Bi2MoO6 composite microspheres for methylene blue (MB) simulated dye wastewater. The experimental results showed that g-C3N4/Bi2MoO6 composite was successfully synthesized on the surface of yeast templates through hydrothermal-template sacrifices method, and the as-obtained microspheres with diameter at about 8 microns were of good dispersity. The surface of the g-C3N4/Bi2MoO6 microspheres were composed of flower-like nano-clusters, and the specific surface area of composite sample reached 11.6007 m2/g. The results of photocatalytic experiments verified remarkable visible-light driven photocatalytic performance of flower-like g-C3N4/Bi2MoO6 microspheres for methylene blue simulated dye wastewater. The degradation efficiency for the MB simulated dye wastewater at initial concentration of 15 mg/L was beyond 96%, when the as-prepared photocatalyst was added at dosage of 1 g/L and the mixture was irradiated under visible light for 120 min. Mechanism analysis demonstrated that the formation of Z-type heterojunction between g-C3N4 and Bi2MoO6 on the flower-like surface of bio-templated microspheres reduced the recombination rate of electronic-hole remarkably and enhanced the visible-light driven photocatalytic efficiency for simulated dye wastewater significantly.