Objective To compare the efficacy between endoscopic ultrasound and abdominal ultrasound in the diagnosis of calculi of bile duct. Methods The clinical data of 30 patients with suspected calculi of bile duct were retrospectively analyzed, and all patients underwent endoscopic ultrasound, abdominal ultrasound, and endoscopic retrograde cholangiopancreatography/endoscopic duodenal papillary sphincterotomy. With the endoscopic retrograde cholangiopancreatography/endoscopic duodenal papillary sphincterotomy as the gold standard in the diagnosis of calculi of bile duct, the efficacy between endoscopic ultrasonography and abdominal ultrasound in the diagnosis of calculi of bile duct was compared. Results The accuracy of endoscopic ultrasound in the diagnosis of calculi of bile duct was higher than that of abdominal ultrasound (P<0.05). The results of endoscopic ultrasound in the diagnosis of calculi of bile duct were associated with those of the gold standard (P<0.05), while the results of abdominal ultrasound were not(P>0.05). There was no statistically significant difference in the positive result between the gold standard and endoscopic ultrasound or between the gold standard and abdominal ultrasound in the diagnosis of calculi of bile duct (all P>0.05). The results of endoscopic ultrasound in the diagnosis of calculi in different parts (at the end of the common bile duct, above the common bile duct, and at the middle and lower part of the common bile duct) and in different sizes (diameter ≤0.5 cm, 0.5-1.0 cm, and >1.0 cm) were associated with those of the gold standard (all P<0.05), while the results of abdominal ultrasound were not (all P>0.05). Conclusion Endoscopic ultrasound has higher diagnosis efficacy for calculi of bile duct than abdominal ultrasound, and its diagnostic results of calculi of bile duct in different parts and sizes are associated with the gold standards', which has a certain guiding value for clinical treatment.