Abstract: In the present work, nano-ceramic tile wastes were used as accessible, nontoxic and inexpensive support materials for the immobilization of phosphomolybdic acid (H3PMo12O40) in 1–20 wt% by an impregnation method. The novel and active heterogeneous solid acid nanocatalyst, so-called nano-ceramic tile waste, supported phosphomolybdic acid (n-CTW/PMA) well characterized by the aid of FT-IR, XRD, FE-SEM, EDX and TGA analyses. The catalytic activity of the as-prepared catalyst was probed in the chemoselective oxidation of sulfides to sulfoxides using 30% H2O2 as green oxidant at room temperature under solvent-free conditions. Optimization of the reaction conditions was accomplished by the aid of central composite design (CCD) as one of the most applicable response surface methodologies. The results showed that the catalyst with 11 wt% PMA loading led to high conversion rates and yields (97%). Besides, the noticeable advantages of this new catalyst were as follows: highly active and selective, low-toxic and -cost, available and stable, recoverable and reusable for several times.