Objective　To measure the thickness of cortical bone of the posterior border, the angle and the inferior border of mandible, and provide anatomical basis for plastic surgery.  Methods　60 healthy young women undergone mandible MSCT examination, then the multiplanar reconstruction (MPR) was done, followed with the measurement of the exterior, interior and marginal cortical bone thickness of the posterior border, the angle and the inferior border of mandible. The data were analyzed by SPSS13.0.  Results　The exterior, interior and marginal cortical bone thickness of the left posterior border of mandible were (2.13±0.29） mm，（2.89±0.35） mm，and （4.40±0.66） mm; The exterior, interior and marginal cortical bone thickness of the left angle of mandible were （2.15±0.35） mm，（2.91±0.36） mm and （5.80±1.23） mm；The exterior, interior and marginal cortical bone thickness of the left inferior border of mandible were (2.20±0.41）mm，（3.02±0.42）mm and (4.31±0.68）mm respectively. The above parameters of the right were (2.14±0.25）mm，（2.73±0.29）mm and （4.17±0.59）mm; （2.25±0.25）mm，（2.76±0.32）mm and （5.60±1.06） mm；（2.40±0.39）mm，（2.99±0.41）mm and （4.15±0.65）mm respectively. Significant difference can be find among the thickness of exterior cortical bone of bilateral posterior border of mandible, the thickness of exterior cortical bone of bilateral angle, and the thickness of interior cortical bone of the inferior border of bilateral mandible.   Conclusions　The measurement of cortical bone thickness of the posterior border, the angle and the inferior border of mandible by Multi-slice computed tomography is valuable to reduce the complications during the plastic surgery.