 SnO nanoparticles as an efficient and recyclable catalyst have been successfully prepared and were used as a heterogeneous catalyst for the one-pot synthesis of 3,4,5-substituted furan-2(5H)-ones by the three-component reaction of aniline derivatives, dialkyl acetylene dicarboxylate, and aromatic aldehydes in ethanolic medium at room temperature. This work consistently has the advantages of excellent yields, short reaction time, simple workup, and recyclability of the catalyst up to six runs without appreciable loss of activity.