The polymorphic phosphorus materials such as amorphous red and black ones have been used as the anodes for alkali‐ion batteries. As the research field of 2D materials is pioneered, the fibrous red and violet phosphorus begin to be investigated and predicted for various devices. Meanwhile, they are not only applied to the active materials of electrodes but also the formation of protective layers for battery application. This article briefly introduces the primary allotropes of phosphorus, their research progress, and their potential for the application of alkali‐ion batteries. Next, the recent studies concerning their applications of electrodes and protective layers for alkali‐ion batteries are discussed in detail. Finally, the merits and drawbacks of preparation approaches, the strategies for improvement of battery performance, and the urgent challenges as well as possible solutions for future development of alkali‐ion batteries using the electrodes or protective layers made from phosphorus materials, are summarized.