Sweet's syndrome is an uncommon reactive dermatoses characterized by fever, polymorphonuclear leukocytosis, painful erythematous plaques, and dense dermal infiltrate of neutrophils. Sweet's syndrome can be associated with several diseases, including infectious diseases, malignant tumors, and autoimmune diseases. However, no case of Sweet's syndrome associated with Sjogren's syndrome (SjS) has been reported in Korea. A 44-year-old woman presented with acute pustular rashes and fever. The patient had multiple papulopustular skin rashes, and complained of fever, chills, and headache. Our patient had the characteristic clinical and histopathological features of Sweet's syndrome, in association with SjS, diagnosed by salivary gland scan, positive anti-SS-A/SS-B antibody, and sicca symptoms simultaneously. Thus, we report on a case of a patient with Sweet's syndrome with concomitant diagnosis of SjS.