Vaterite thin film has been prepared by solvothermal treatment of calcium chloride and urea in the presence of ethylene glycol at 100 degreesC for 12-36 h. The resulting film consisted of uniform vaterite crystals with the particle size of 0.5 mum. and was homogeneous without visible pores. The film was characterized by powder X-ray diffraction, scanning electronic microscopy and Fourier transform infrared techniques. Ethylene glycol was found playing a key role in the vaterite film formation, which served not only to produce environment with high concentration of calcium ion but also to stabilize the metastable vaterite crystal, preventing its transformation into aragonite and calcite. A possible mechanism for the formation of vaterite films on glass substrate under solvothermal conditions is proposed.