Positron emission tomography (PET) using 2-[18F]fluoro-2 deoxy-D-glucose (FDG) was performed on two uterine cervical cancer patients in whom recurrent tumors, one pelvic and the other at the vaginal wall had not been precisely diagnosed using the usual imaging examinations. One recurrence was confirmed by the acccumulation of FDG to the pelvic mass as detected by magnetic resonance imaging (MRI). During chemotherapy, changes in FDG-PET findings were detected earlier than those in MRI. In the other, PET detected a recurrent tumor that could not be found by MRI, and was also useful for evaluating chemotherapeutic effects. These cases suggest that PET with FDG can be a useful examination not only for diagnosing recurrent cervical cancer after radical hysterectomy, especially pelvic recurrence, but also for evaluating chemotherapeutic effects on recurrent cancers.