Objective To study the dosimetric peculiarity of 3D intracavitary brachytherapy in the application of endometrial carcinoma by comparing with traditional 2D plans.Method 39 times of 3D intracavitary brachytherapy treatment plans of 11 patients who were diagnosis as Endometrial carcinoma were retrospectively analyzed with re-planning two-dimensional treatment plan according to traditional method, the dose volume histogram (DVH) parameters such as the target dose volume parameters V150 and D90, the 2-cc doses to organs such as bladder、 small intestine、 rectum and sigmoid and the total reference air kerma TRAK were analyzed.The differences between the two groups are compared by paired samples T test.Results For small target (V<60 cm3) , there is no statistically significant difference between 2D and 3D plans, the D90 is (551.17 ? 90.33) cGy and (574.15 ? 117.18 cGy, respectively (P=0.390).With the increase of target volume, the D90 came to be significantly different(P=0.001), high dose region V150 for 3D and 2D plans is (51.05? 21.61) cm3 and (53.41? 11.71) cm3 , respectively (P=0.482).With the target volume larger than 60 cm3 ,compare to 2D plans, the 3D plan can increase the target coverage as well as OAR dose except for small intestine(P=0.128).In addition, with different plan mode, the BMI did not affect the crisis organ dose such as rectum、 small intestine、 bladder and sigmoid, the P value is 0.239、0.198、 0.744 and 0.834,respectively.Conclusions For Endometrial carcinoma, compared with traditional two-dimensional plans, the 3D intracavitary brachytherapy treatment plans can significantly improve the target coverage and avoiding overdose of organs, clinical curative effect and side effect still needs further observation.