Our current work's primary goal is to create novel heterogeneous gallium sulfide (Ga2S3) nanocatalysts and investigate their catalytic activity in the synthesis of 3,3-(arylmethylene)-bis-(4- hydroxycoumarin) derivatives without use of solvent. FT-IR, XRD, SEM, and EDX analysis characterized the synthesized gallium sulfide (Ga2S3) nanomaterial catalysts. This method's main benefits are its short reaction time, solvent-free conditions, extremely mild reaction conditions, good product yield, and, most importantly, its ability to recover catalysts after at least four runs.