A 79-year-old male with acute myelogenous leukemia developed acute right knee arthritis during admission, after the use of broad-spectrum antibiotics before chemotherapy. The initial synovial fluid sample appeared to be mildly inflammatory with a low white cell count. The fungal septic arthritis was not diagnosed until Candida tropicalis, a rare species of Candida, was isolated in the synovial fluid. Although fluconazole is effective in treating the microorganism, the untreated leukemia rendered the infection incurable and led to the growth of fluconazole-resistant Candida krusei. We reported the unusual case of fungal arthritis and reviewed the literature.