AbstractActive cuprous oxide materials are synthesized from CuSO4.5H2O using sodium stannite as reducing agent in the presence of various stabilizers, viz., cetyl trimethyl ammonium bromide, sodium dodecyl sulphate, and polyvinyl pyrrolidone. The synthesized cuprous oxide materials are well characterized by powder X‐ray diffraction and Fourier transform infrared spectroscopy to ascertain their identity, while field emission scanning electron microscopy and energy‐dispersive spectroscopy analysis were used to study their morphology and composition, respectively. We have compared the catalytic prowess of the various cuprous oxide materials in the cycloaddition reaction of alkynes and azides to synthesize 1,4‐disubstituted‐1,2,3‐triazoles. A wide variety of substitutions can nicely be tolerated in our optimized reaction conditions to produce very good to excellent yields of the corresponding triazoles in water at 55 °C. The reactions are carried out in water without any assistance of organic cosolvent or other additives, which renders the catalytic method as economical and environment friendly.