Primary effusion lymphoma-like lymphoma (PEL-LL) shows a unique clinical presentation, characterized by lymphomatous effusions in the body cavities. PEL-LL may be associated with hepatitis C virus infections and fluid overload states; and owing to its rarity, no standard therapies have been established. We report a case of a 55-year-old woman who developed PEL-LL during treatment with dasatinib, for chronic myeloid leukemia (CML). She presented to our hospital with dyspnea lasting for approximately a month and showed pericardial and bilateral pleural effusions. The pericardial effusion was exudative, and cytopathological and immunophenotypic examinations showed numerous CD 20-positive, large atypical lymphoid cells, which were also positive for the Epstein-Barr virus gene. No evidence of lymphadenopathy or bone marrow infiltration was found. We diagnosed PEL-LL, immediately discontinued dasatinib, and performed continuous drainage of the pericardial effusions. Complete response was achieved, and remission was maintained for 15 months. Two months after discontinuation of dasatinib, she was administered imatinib and a deep molecular response for the CML was maintained. PEL-LL occurring during dasatinib treatment is rare. We compared the results of previous reports with this case, and found that early diagnosis of PEL-LL, discontinuation of dasatinib, and sufficient drainage can improve the prognosis of PEL-LL.