Abstract: Objective:To analyze the ultrasonic features and causes for misdiagnosis of primary carcinoma of gallbladder(PCG) in order to improve the diagnosis rate.Methods:Thirty cases of PCG proved by pathology after operation were reviewed retrospectively,ultrasound examination after 8 h fasting.The shape,size,wall thickness and intracavity echo of the gallbladder,the liver and the exterior and interior of the hepatic bile were observed carefully to find out the ultrasonic features of PCG,and the causes for misdiagnosis were analysed.Results:In the 30 cases of PCG,18 were diagnosed by ultrasonography and 12 were misdiagnosed.Twenty-four of the cases were complicated with gallbladder stones and 6 cases gallbladder polyps,4 cases were found to have liver metastasis and 2 hilar lymph nodes.Conclusions:The ultrasonic manifestation of PCG is complex and diverse.Color Doppler ultrasound may help to improve the early diagnosis rate of PCG and reduce misdiagnosis.