This paper reports the influence of solvent treatment on the behaviour of 0-3 piezoelectric composite films. In our experiments, 0-3 composite piezoelectric films are prepared and treated in a solvent for a period of time, and their piezoelectric properties are measured. It is found that the characteristics of composite piezoelectric films are significantly influenced by the solvent treatment. In the case of treated specimens, the piezoelectric properties are increased more than those of virgin specimens, d 3 3 values being 1-5 times larger than those of virgin specimens. This influence of solvent treatment on the behaviour of 0-3 composite piezoelectric films is analysed in the light of chemical coupling-induced percolation. This strongly suggests that it is possible to obtain 0-3 composite piezoelectric films with excellent piezoelectric parameters in this way.