Objective Tumor angiogenesis plays an important role in the development and occurrence of the tumor, and has great impact on tumor biological behavior and prognosis.Phase contrast imaging is used to observe the morphology of the vessel network in three-dimensions.Methods The orthotopic cancer model in nude mice is established by orthotopic implantation of cancer tissue block.The mice are divided into control group and cancer group.The imaging data are enhanced, and the blood vessels are segmented and three-dimensional reconstructed.Then we calculate the micro vessel density (MVD).Results Phase contrast imaging can demonstrate the micro vessel morphology of stomach cancer.The MVD of control group is lower than that of the tumor surface area in the cancer group( P<0.001), which proves that the tumor area has much richer blood supply.Conclusions The results comprehensively show the condition of tumor angiogenesis, which is helpful to evaluate the malignant degree and metastatic potential of gastric cancer.This project is also important for establishing therapeutic strategy, prognosis assessment and pharmaceutical effect evaluation of anti-angiogenesis therapy.