Granulocyte colony-stimulating factor (G-CSF)-producing nonhematopoietic malignancies have been reported in various organs, and most of them have been associated with poor clinical outcome. However, because of the rarity of the reported cases, information regarding the G-CSF-producing gynecological malignancies is limited. We report the first 2 cases of G-CSF-producing cervical adenocarcinomas, which exhibited an aggressive clinical course. At initial diagnosis, both patients exhibited marked leukocytosis without an obvious sign of infections. Of these, one was initially treated with definitive radiotherapy and the other was treated with radical surgery. However, both of these patients experienced recurrences in a short period and died from disease progression in less than 6 months. According to the facts that the tumor cells were positive for G-CSF, the elevated serum level of G-CSF, and their clinical course correlated well with the white blood cell count, we concluded that these tumors were G-CSF-producing cancers. These cases strongly indicate the aggressive nature of the G-CSF-producing cervical adenocarcinomas.