Abstract: The equation for the momentum and the wavelength for the matter wave is derived in two intuitive ways. The first way is to use the Lorentz transformation to obtain the inherent time difference between the head and tail of the moving particles, and then obtain the corresponding wavelength for the material wave through its phase difference and the length of the particle occupied in space. The second way is to obtain the equation by calculating the traveling wave adapted to the phase change of the particle. These two derivation methods are intuitive and helpful to beginners to understand the physical image of the matter wave.

Key words: matter wave equation, Lorentz transformation, relativistic effect