Objective: To examine the prevalence of female sexual dysfunction (FSD) in gynecologic cancer survivors. Methods: A cross-sectional observation survey recruited women aged 18-65 years old who were diagnosed with gynecologic cancers and underwent surgery, radiation, chemotherapy, or combined modalities. Data were collected from September 2019 to March 2020 by the Thai version of the female sexual function index questionnaire to define FSD. The survey contained six domains: desire, arousal, lubrication, orgasm, satisfaction, and pain. Results: Of the 98 women included in the study, the mean age was 48.7 AE 10.6 years old. Two-third (67.3%) of the participants was premenopausal, had been diagnosed with ovarian cancer, and had early-stage gynecologic cancers. Fifty-eight of 98 (59.2%) participants were sexually active in the past 4 weeks before the survey. Among those, 89.6% had FSD. The median scores in the FSD group were significantly lower than those in the non-FSD group in all six domains, namely, desire, arousal, lubrication, orgasm, satisfaction, and pain (p < 0.05). There was no statistically significant difference observed between participants with and without FSD in terms of age group, cancer-related data, or sexual behavior data, except participants who had good/ excellent relationships with their partners, which impacted FSD (p = 0.01). Conclusions: This study discovered the high prevalence (89.6%) of hidden issue of "female sexual dysfunction" in Thai gynecologic cancer survivors. The good/excellent relationships with their partners affected the FSD who were sexually active in the past 4 weeks before the survey.