The hydrothermal synthesis and magnetic entropy change for the perovskite manganite La0.7Ca0.2Sr0.1MnO3 have been studied. The La0.7Ca0.2Sr0.1MnO3 can be produced as phase-pure, crystalline powder in one step from solutions of metal salts in aqueous potassium hydroxide solution at a temperature of 240 degrees C in 72 h. Scanning electron microscopy shows that the materials are made up of cuboid-shaped or rod-shaped particles with typical dimension of 4.0 mu m. Heat treatment is necessary to improve the magnetocaloric effect for the hydrothermal sample. The maximum magnetic entropy change (1 Delta S(M)l) for the sample annealed at 1200 degrees C for 6 h is 2.85 J kg(-1) K-1 at the magnetic field change of 2.0 T and 2.23 J kg(-1) K-1 at the magnetic field change of 1.5 T at 315 K. The hydrothermal synthesis method is a feasible route to prepare high quality perovskite material for magnetic refrigeration application. (c) 2006 Elsevier B.V. All rights reserved.