A simple and highly efficient protocol was developed for one-pot synthesis of polyfunctionalized spirothiazolidin-4-ones using sulfonated mesoporous silica (MCM-SO₃H) as a heterogenous and reusable acidic catalyst. In comparison to the reported synthetic methods for the synthesis of thiazolidin-4-one and spirothiazolidin-4-one derivatives, this strategy provides superior yields under mild conditions, while avoiding hazardous solvents.