Ferroelectric bismuth vanadate (B2VO5.5) thin films were successfully fabricated on n-type Si (100) substrate by sol-gel method. The microstructures of the films were investigated by x-ray diffraction and atomic force microscopy. The results indicate that B2VO5.5 thin films show a good match with the n-Si substrate and a high c-axis preferred orientation with a uniform grain distribution. The investigation on the electrical properties of B2VO5.5 thin films indicates that B2VO5.5 thin films show good capacitance-voltage characteristics, and the memory window is larger than 0.4V when the gate voltage is ±4V. The leakage current density is about 5×10-8 Acm-2 when the applied voltage is 3.2V. The dielectric constant and dielectric loss measured at 1 kHz are 95 and 0.22, respectively. All the results indicate that Bi2VO5.5 thin films have potential applications in ferroelectric memory devices.