The invention discloses an oscillating water column self-exciting type wave energy composite power generation device based on the Karman vertex street effect and belongs to the technical field of sustainable power generation. The composite power generation device comprises an upper shrinkage gas channel, an upper cavity body, a lower shrinkage gas channel and a lower cavity body which are sequentially connected from top to bottom. A gas input and output opening is formed in the upper portion of the upper shrinkage gas channel. A sea water input and output opening is formed in the lower portionof the lower cavity body. A sleeve is arranged in the upper cavity body. The sleeve divides the upper cavity body into a left chamber, a middle chamber and a right chamber. An upper streaming cylinder and a lower streaming cylinder are arranged in the sleeve. Multiple dielectric elastomer films sequentially arranged are arranged between the upper streaming cylinder and the lower streaming cylinder. First permanent magnets are arranged on the two sides of the middle position of each dielectric elastomer film correspondingly. Second permanent magnets corresponding to the first permanent magnetsone to one and a piezoelectric cantilever beam used for installing the second permanent magnets are arranged in the left chamber and the right chamber correspondingly. The composite power generationdevice can work in a humid environment for a long time, so that permanent and continuous electric energy is provided.