A facile one-pat hydrothermal synthesis of hollow ball-like ZnS nanostructures is reported using cysteamine, an ecofriendly sulfur source. Following similar protocol, a heterostructure of RGO-ZnS nanocomposite have been synthesized. The as-synthesized samples are structurally and optically characterized using different techniques. The photo catalytic activity of RGO-ZnS has been found to be similar to 9% higher than that of ball-like ZnS nanostructures at a dose of 0.4 g/L. This result is attributed to the improved charge transport by hindering charge recombination of photoinduced excitons. One of the significant findings of this work is that the model anionic dye degraded better under alkaline condition with ZnS whereas the trend is reversed for RGO-ZnS composite. The removal efficiency of both the systems is allied with structural, morphological, and optical properties to understand the underlying mechanism of synthesis as well as photocatalysis process.