The invention discloses a flexible three-dimensional porous carbon material and a preparation method and application thereof. The method adopts a commercial melamine sponge which is low in cost as a three-dimensional flexible carbon skeleton template, and coal pitch as a carbon source, and obtains the flexible three-dimensional porous carbon material which is high in conductivity and high in specific surface area in one step through a KOH activation method; and the material is simple in preparation process, low in cost and suitable for industrial application. The material serves as a super capacitor electrode material, and has larger energy density, power density and excellent cycle stability.