Microcapsules self-repairing polymeric composites belong to a new kind of smart materials. In this work, microcapsules used for polymeric composites self-repairing were prepared by in-situ polymerization. Optical microscopy, scanning electronic microscopy (SEM), fourier transfer infrared spectroscopy (FT-IR), and thermal gravity analysis (TGA) were used to determine the properties of prepared microcapsules such as grain size and their distribution, wall thickness, content of core materials and thermal performances of microcapsules. Results showed that the average grain size was 210 μm and the wall thickness was in the range of 1.8-5 μm depending on agitation rate. Thermal analysis indicated that the repairing agent’s core materials were encapsulated in microcapsules.