The present invention discloses a codec-based geometric division mode prediction method, device, storage medium and terminal. The method includes: performing optimal mode prediction on the current coding block, and selecting the most probable mode set from the total mode set ; Make a mode decision in the most probable mode set; write the index of the optimal mode obtained by the final decision in the most probable mode set into the code stream. Make mode decisions from the total mode set, use an identification bit to identify whether the optimal mode obtained by the final decision is in the most probable mode set, if it is in the most probable mode set, write its index in the most probable mode set codestream, otherwise write its index in the total mode set into the codestream. Therefore, by adopting the embodiment of the present application, it is possible to reduce the encoding overhead of the division mode, improve the compression performance, and reduce the complexity of the encoding end.