Abstract: Immunoglobulin G4-related disease (IgG4-RD) is a rare systemic immune-mediated disorder characterized by infiltration of IgG4-positive plasma cells and multiorgan fibrosis. Among them, cases with multiple pancreatic cystic lesions as the prominent manifestation are relatively rare, and they are easily misdiagnosed as pancreatic tumors or pancreatitis in clinical practice. Herein, we report one patient with IgG4-RD admitted to Peking Union Medical College Hospital. The patient initially presented with multiple pancreatic cystic lesions and aneurysmal dilatation of the abdominal aorta, accompanied by markedly elevated serum IgG4 levels. Combined with pathological findings from submandibular gland biopsy, the diagnosis of IgG4-RD was ultimately established. After treatment with a regimen of glucocorticoids combined with cyclophosphamide, the patient′s condition improved. Meanwhile, we performed a literature review of cases with IgG4-RD-related pancreatic cystic lesions, aiming to improve clinicians′ understanding of this rare disease phenotype.