Disclosed herein are a method, an apparatus, and a storage medium for image encoding/decoding using geometric partitioning. A target block may be geometrically partitioned, and multiple partitioned regions may be generated from geometric partitioning. Each partitioned region may have a non-square and a non-rectangular shape. Different prediction schemes may be applied to different partitioned regions. The different prediction schemes for multiple partitioned regions may be signaled as explicit information, and may be derived using information about a coding parameter for the target block or the like.