Background:With the progress and widely application of endoscopic techniques,the prevalence rate of periampullary diverticulum (PAD)is increasing in recent years. However,the results of studies investigating the correlation of PAD and its types with common bile duct (CBD)stone are different. Aims:To investigate the influence of PAD and its types on CBD stone. Methods:A total of 1524 consecutive inpatients who underwent diagnostic and therapeutic ERCP for pancreatobiliary diseases from Jan. 2014 to Dec. 2016 at the General Hospital of Xinjiang Military Region of Chinese PLA were enrolled and divided into two groups according to the presence or absence of PAD. Patients in PAD group were further classified into 3 subgroups by the papilla's location with respect to the diverticulum. Their clinical data were collected and retrospectively analyzed. Results:The proportion of elderly patients (≥60 years old)in PAD group was 82. 2% (310 /377),which was significantly higher than that in non-PAD group [60. 8% (697 / 1147),P < 0. 05]. The prevalences of CBD stone,gallstone associated with CBD stone,post-cholecystectomy and recurrent CBD stone were higher and the size of CBD stone was larger in PAD group than in non-PAD group (P all < 0. 05). Furthermore,stratified analysis revealed that the CBD stone was more prevalent and the size of stone was larger in type Ⅱ PAD than in type Ⅰ and type Ⅲ PAD (P <0. 05), while recurrent CBD stone was more frequent in type Ⅰ and type Ⅱ PAD than in type Ⅲ PAD (P < 0. 05). Multivariate analysis indicated that the elderly and PAD were the risk factors for recurrence of CBD stone,and cholecystectomy was a protective factor. Conclusions:The elderly is predisposed to PAD. PAD and its types are associated with the development and recurrence of CBD stone. CBD stone is more prevalent in patients with PAD especially type Ⅱ PAD. The size of stone is larger and the post ERCP recurrence rate is high in type Ⅱ PAD.