Objective To investigate the sonographic features of chorionic bump in early pregnancy and its clinical significance. Methods This was a retrospective analysis. The sonographic features of chorionic bump, subchorionic hematoma and normal pregnancy by transvaginal ultrasound examination were compared. Then followed-up the pregnancy outcome and analyze its influence on pregnancy outcome. Results Chorionic bump which is an local irregular ,convex bulge from the choriodecidual surface into the first-trimester gestational sac, and there was no blood flow signal. Among 33691 cases of early pregnancy, 60 cases with chorionic bump and 2257 cases with subchorionic hematoma. The detection rate was 0.178% and 6.70% respectively. Of the 38 cases with chorionic bump, 8 (21.05%)embryo development arrested vs 17/220(7.72% )in the subchorionic hematoma group (P=0.010), and vs 21/235 (8.93%)in the normal pregnancy group( P=0.025).There were no statistical significance in the incidence of embryo development arrest between the subchorionic hematoma group and the normal pregnancy group (P=0.641).