The invention provides a lead titanate coating and a preparing method thereof. According to the method, mixed powder is sprayed on the surface of a matrix, and through polarization, the lead titanate coating is acquired. The mixed powder comprises PbTiO3 powder, PbO powder and Al powder. Lead titanate (PbTiO3) is a kind of ferroelectric material, and can be used for preparing a piezoelectric sensor. Besides, the PbO powder and the Al powder are added, so that the piezoelectric property of the lead titanate coating can be improved. Since the lead titanate coating prepared by the present invention can be combined with the matrix closely and the intensity of piezoelectric signal is high, it can be widely applied to mechanical parts, such as a piston ring, a cylinder, a gear, and the like, to dynamically monitor the service situations of the parts better.