To investigate whether pSS patients with hyperglobulinemia have an increased risk of all-cause mortality.Patients who registered in Chinese Rheumatism Data Centre from May 2016 to July 2021, and met the 2002 AECG criteria or 2016 ACR/EULAR classification criteria for SS were included. Hyperglobulinemia was defined as any elevated serum levels of IgG, IgA, or IgM. The primary outcome was all-cause death. Data for demographic and clinical characteristics, laboratory results, disease activity, damage scores, treatments were evaluated.A total of 9,527 pSS patients were included in the analysis, of whom 4,236 (44.5%) had at least one kind of elevated immunoglobulin level among IgG, IgA, and IgM. Patients with hyperglobulinemia had a significantly increased risk of death (crude HR 2.60; 95%CI 1.91-3.55; adjusted HR 1.90; 95%CI 1.20-3.01). Risk of death was positively correlated with IgG level (P trend <0.001). The 5-, 10-, and 15-year survival rates of patients with hyperglobulinemia were 96.9%, 92.3%, and 87.9%, respectively, and significantly lower than the corresponding rates of 98.8%, 97.9%, and 96.4% in patients without hyperglobulinemia.Hyperglobulinemia is an independent risk factor for increased all-cause mortality in pSS patients. Risk of death is positively correlated with IgG level.© Japan College of Rheumatology 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.