A picture prediction method includes: determining whether a merge mode is used for a current picture block; when the merge mode is used for the current picture block, determining whether a regular merge mode is available; when the regular merge mode is unavailable, and a high-layer syntax element sps_triangle_enabled_flag corresponding to a triangle partition mode (TPM), indicates that the TPM is forbidden to be used, determining a combined intra and inter prediction (CIIP) mode as a target merge mode used for the current picture block and predicting the current picture block based on the target merge mode.