The invention refers to negative electrode plate, preparation method thereof and electrochemical device. The negative electrode plate comprises: a negative current collector; a negative active material layer disposed on at least one surface of the negative current collector, the negative active material layer comprising opposite first surface and second surface, wherein the first surface is disposed away from the negative current collector; and an inorganic dielectric layer consisting of an inorganic dielectric material disposed on the first surface of the negative active material layer. The negative electrode plate provided by the application is useful in an electrochemical device, and can result in an electrochemical device having simultaneously excellent safety performance and cycle performance.