The morphology of the toughening master batches (TMBs) for polypropylene (PP) was characterized by means of transmission electron microscopy and polarizing microscopy, and the melt flow rate and melting point were investigated as well. Results indicated that the TMBs prepared by using dynamic vulcanization and polymer–bridge conjunction techniques took on a very special morphology. The morphology of the TMBs was formed through microphase separation with PP component as the continuous phase, shaping very small crystallites and with elastomer component at the dispersed phase having a cellular structure containing some PP. Such a morphological characteristic is essentially different from the packaged morphology formed by flow encapsulation during the process of thermal mechanical blending. The data of melt flow rate showed that the TMBs had good processing properties adequate for being processed into polypropylene composites with both excellent toughness and balanced rigidity. The melting temperature of the TMBs determined by differential thermal analysis is lower than that PP, providing additional evidence of the chemical bonding among some elastomers and PP.