Type I diabetic patients are susceptible to pancreatic cancer relative to the normal group. Pancreatic cancer is a malignant tumor of the digestive tract with insidious onset, rapid progression, extremely poor treatment effect and prognosis, and its incidence is continuously increasing worldwide. Depending on the location and size of the tumor, the organs involved and its severity, pancreatic cancer patients may manifest epigastric or back pain, nausea, abdominal distension, jaundice, new-onset diabetes mellitus, weight loss, and changes in stool properties, etc. Occasionally, patients with acute pancreatitis as the main manifestation are seen. Studies have shown that the risk factors associated with the development of pancreatic cancer include obesity, type 2 diabetes mellitus, smoking, alcohol consumption, etc. 5% to 10% of patients with pancreatic cancer have genetic susceptibility factors, such as Peutz-Jeghers syndrome (STK11 gene), familial pancreatitis (PRSS1, SPINK1, CFTR gene), melanoma-pancreatic cancer syndrome (CDKN2A gene), etc. An analysis of diabetic patients showed that the incidence of liver, pancreatic, renal, endometrial, and ovarian cancers was higher in patients with type 1 diabetes than in the general population, while the incidence of prostate cancer was lower than in the general population. The incidence of pancreatic cancer was 53% and 25% higher in men and women with type 1 diabetes than in the general population, respectively. Therefore, patients with type 1 diabetes mellitus have a greater likelihood of developing pancreatic cancer, but it is not conclusive. Patients are advised to pay attention to follow-up observation, and if there is any abnormality, it is recommended to go to regular hospitals for comprehensive assessment of the condition and follow the doctor’s instructions to cooperate with the treatment, so as to avoid delaying the condition.