关于波速与波长变换，一些文献中虽有论述，但所得表达式太复杂而不宜记忆，且未涉及其物理意义．本文由四维波矢的洛伦兹变换来分析这一问题，通过引入波速因子和综合速度因子的概念，得到容易记忆的简单表达式，并力求阐明其物理意义，最后说明其应用．

Regarding wave speed and wavelength transformation, although it has been discussed in some literatures, but the obtained expressions is too complex to be remembered, and its physical significance is not involved. This article analyzes this problem by the Lorentz transformation of four-dimensional wave vector, through introducing the concept of wave speed factor and comprehensive velocity factor, the simple expressions that are easy to remember is obtained, and strive to clarify its physical significance, and finally explain its application.