Objective To analyze the ultrasound imaging features and the reasons of misdiagnosisS of ectopic pregnancy occurred in rare location, and to explore the clinical value. Methods The ultrasound imaging features of 325 patients, who were diagnosed with rare ectopic pregnancy by surgical pathology from Jan.2015 to Aug.2017 year in our hospital, were analyzed in this study, and the reasons of misdiagnosis and missed diagnosis and the methods and skills of ultrasonic diagnosis were also discussed. Results The most common rare ectopic pregnancy was uterine scar pregnancy, which accounted to 37.5%; the second one was interstitial tubal pregnancy with an occurrence rate of 37.2%, and 4 cases of misdiagnosis, 1 cases of missed diagnosis in; ovarian pregnancy occurred in 7.4% of cases; cornual pregnancy occurred in 11.7% of cases with 5 cases misdiagnosed and 1 cases missed; cervical pregnancy occurred in 1.8% of cases with 2 cases misdiagnosed; pelvic pregnancy occurred in 1.5% of cases with 1 case missed; intramural pregnancy occurred in 0.9% of cases with 1 cases misdiagnosed ; the occurrence rates of rudimentary uterine horn pregnancy and abdominal pregnancy were 0.9% each. Conclusion The detection rate might be improved by fully understanding the ultrasonographic features