Objective To analyse the limitations of oral ultrasonic contrast agent for gastric carcinoma to improve the accuracy of diagnosis. Methods Medical records of 119 patients with gastric cancer were retrospectively reviewed to identify misdiagnoses and their contributing factors during preoperative ultrasound of 120 cancer nodules using oral ultrasonic contrast agent. Results Of the 120 nodules， four were not detected，34 （28.3%） were misdiagnosed in the T stage，60 （50.4%） were misdiagnosed in the N stage，and 4（3.4%） were not detected in the M stage. Conclusion Understanding the reasons for preoperative misdiagnosis of gastric carcinoma using oral ultrasonic contrast agent and adopt corresponding measures may improve diagnostic accuracy.