Rothia mucilaginosa is a bacterium derived from the upper respiratory tract microbiota, which is rarely associated with infections in immunocompromised patients suffering chronic lung diseases, mainly pneumonia and bacteremia. Its treatment is generally based on the use of β-lactams. The case study of a kidney transplant patient using immunosuppressive drugs, who developed a disseminated Cryptococcus neoformans infection, is described. After starting antifungal therapy, he presented with fever, appearance of new radiological infiltrates and acute respiratory failure, demonstrating a positive culture for R. mucilaginosa in a study with bronchoalveolar lavage, ruling out other etiologies. He evolved favorably after the use of meropenem, with good clinical response and resolution of radiological infiltrates.