INTRODUCTION: Serratia marcescens is a Gram-negative bacillus which belongs to the family Enterobacteriaceae. It is a facultative anaerobe and produces red pigment at room temperature. It naturally occurs in soil and water as well as the intestines, and it is responsible for nosocomial infections. There have been few reports about community acquired pneumonia of Serratia.CASE PRESENTATION: This report presents a 37-year-old man with hemoptysis, fever, and shortness of breath. The clinical and laboratory examinations revealed that the patient had pseudohemoptysis due to S. marcescens pneumonia, on an immunocompromised pattern, because of the coexistence of sarcoidosis (stage 1).CONCLUSION: Appropriate antibiotic therapy for Serratia was administered, and the patient's symptoms regressed. The patient is healthy and asymptomatic after 1-year follow-up. To the best of the authors' knowledge, this is the first reported case of a pseudohemoptysis in a patient with pulmonary sarcoidosis.