The image processing effect based on morphology is depending on the operation and the structural element. To suppress noise of image and withdraws the edge information. A method which uses multi-element composite structure with dual gradient filter and multiple synthesis methods based on soft morphology was presented. Flexible multi-element composite structure could effectively remove the image noise filtering, and dual-gradient multiplex could improve the detection rate of the image edge. The experimental results show that the method is better than traditional algorithms in suppressing noise and edge detection.