The polycrystalline thin films of (Pb1-xLax)(Zr0.52Ti0.48)1-x/4O3 (PLZT) were fabricated on LNO/Si substrates by sol-gel method. X-ray diffraction showed that PLZT thin films in rhombohedral-tetragonal phase with a preferential (110) orientation can be obtained after a rapid thermal annealing process at 600 ℃. This is further confirmed by Raman spectrum. With the decrease of La content, hysteresis loops of the thin films gradually broaden. Measurement of the photovoltaic effect in the films shows that photovoltage increases gradually with the increase of the content of La from 1% to 6%. It reaches a maximum there and then decreases when the La content is increased furthermore.