Sometimes endometrial polyps, submucosal myomas, and endometrial cancer show similar findings under ultrasonography. The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensional (3D) power Doppler ultrasonography angiography (PDA) between endometrial cancer and uterine parenchyma lumps. The data of the blood flow indices in 3D-PDA including the vascularization index (VI), flow index (FI), and vascularization flow index (VFI) in 40 patients with endometrial cancer and 41 patients with uterine parenchyma lumps (endometrial polyps and submucosal myomas) were retrospectively analysed and compared utilizing Virtual Organ Computer-aided AnaLysis (VOCAL) software. The results showed that all the blood flow parameters (VI, FI, VFI) were significantly higher in women with endometrial cancer than in those with uterine parenchyma lumps (P<0.001). The area under the curve of ROC of VI, FI, and VFI was 0.98, 0.84, and 0.97, respectively. Thus, the best predictor of endometrial carcinoma was VI with a sensitivity of 97.0% and a specificity of 91.0%. The optimal cutoff value of VI was 4.06%. Our data demonstrated that all of the blood flow signal parameters (including VI, FI, and VFI) in 3D power Doppler ultrasonography had significant antidiastole values between endometrial cancer and uterine parenchyma lumps to assist clinicians in properly diagnosing patients.