Abstract A novel ultrasound assisted adsorption protocol for the removal of erythrosine from aqueous solution by tin sulfide nanoparticle loaded on activated carbon (SnS-NP-AC) has been described. The main and interaction of variables (pH, sonication time, adsorbent dosage and initial dyes concentrations) on the removal of erythrosine were studied and optimized by a central composite design (CCD) combined with response surface methodology (RSM). The small amount of proposed adsorbent (0.02 g) is applicable for removal of high content of erythrosine with high removal percentage (> 98%) in short time (4.5 min). Application of ultrasound led to remarkable decrease in adsorption time