Ternary nanocomposites (NCs) comprising Ag-Cu2O supported on glucose-reduced graphene oxide (rGO) with enhanced stability and visible light photocatalytic activity were synthesized via a facile and green approach using Benedict's solution and glucose solution at room temperature without the need of any toxic reagent, surfactant or any special treatment. Besides mild reducing capability to GO, glucose also induces the functionalization of rGO sheets, preventing the aggregation of reduced sheets and providing in situ stabilization to Cu2O. The resulting Ag-Cu2O/rGO NCs showed excellent photocatalytic efficiency for the photodegradation of methyl orange (MO), and the degradation rate was found to be higher than the pristine Cu2O and Cu2O/rGO NCs. Further, for the first time Ag-Cu2O/rGO NCs showed markedly enhanced photocatalytic efficiency for the photodegradation of phenol solution which is mainly attributed to its high electron injection rate and effective separation of electron–hole pairs. Thus, present strategy explores the facile synthesis way of varieties of Cu2O-based NCs materials using harmless reagents and their feasible applications.