The invention discloses a curing forming method and a forming die used for a non-slab composite material part. The method comprises the steps as follows: composite material part blank is arranged on arigid die body which has the same shape with the processing shape and gluing and layer-paving are carried out according to the required dimension; after the layer-paving is finished, the composite material part blank is arranged on the rigid die body; furthermore, surfaces with plane are provided with elastic soft layers; corner pure rubber layers which are connected with elastic soft layer jointseams are arranged at corner profile so as to form a soft die surface; subsequently, vacuum bag auxiliary material is arranged on the soft die surface so as to prepare the vacuum bag curing forming composite material part. By the flexible soft die consisting of rubber-fabrics, the method arranges the composite material part blank on the surface of the soft die after the layer-paving is finished;the method for preparing the vacuum bag curing forming part solves the surface quality problems in the prior art that the non-die surface of the bag-pressing forming composite material part is crapy,accidented and has no gloss and the like, and improves the working efficiency.