The invention discloses a black phosphorus material-based SPPs-effect nanometer resonant cavity and a manufacturing method thereof. According to the invention, the long-term existence problem of contradiction between the optical absorption effect and the thickness of an absorption layer can be solved. The black phosphorus material-based SPPs-effect nanometer resonant cavity comprises a reflectionlayer, a space loss layer, an absorption layer and a nano porous layer. The reflection layer is made of the metal Al material, and the space loss layer is made of the Al2O3 material. The absorption layer is made of the two-dimensional material black phosphorus. The nano porous layer is made of the metal Ag material. The nano porous layer, the absorption layer, the space loss layer and the reflection layer are vertically distributed from top to bottom in sequence. According to the invention, through the application of the black phosphorus material, the optical absorption performance is enhanced. Meanwhile, due to the introduction of the nano porous layer, the obvious SPPS effect is formed at the interface of Ag/Black phosphorus, so that the absorption gain is further improved. The absorption spectrum is expanded and the overall performance of a photovoltaic device is improved. The development of the ultra-thin energy capture and the conversion application can be further promoted.