Multisystem inflammatory syndrome in adults (MIS-A) is a rare sequelae after coronavirus disease 2019 (COVID-19) that is characterized by fever as well as cardiovascular and gastrointestinal disorders. We present the case of an 80-year-old Korean woman with MIS-A who experienced febrile sensations, dyspnea, and whole body pain for 7 weeks after being diagnosed with COVID-19. Initial evaluation revealed heart failure, left pleurisy, and sensory neuropathy, but no evidence of infectious diseases was found. Her symptoms improved quickly after starting systemic glucocorticoid therapy, and inflammatory marker levels decreased. When treating patients with fever after COVID-19, it is critical to suspect MIS-A as one of the differential diagnoses for timely diagnosis and treatment.