Japan has been recognized for its excellent universal health coverage system. However, the migrant population faces many barriers in accessing health services in Japan. Japan hosts around 260,000 international students, mostly from developing countries. Among them, language school students tripled from 2011 to 2017, against the backdrop of labor shortage in Japan. Most of these students are also engaged as cheap laborers and are vulnerable populations with poor access to health services. Several socio-economic and behavioral factors may increase their vulnerability to HIV and prevent them from accessing HIV testing in Japan. We examined the factors associated with access to HIV testing among international students in language schools in Tokyo. We conducted a cross-sectional study among international students studying in Japanese language schools in Tokyo. We collected data from 769 Chinese, Vietnamese, and Nepalese students using a self-administered questionnaire. We measured their access to HIV testing through questions on their knowledge of where to receive HIV testing and utilization of HIV testing. Bivariate and multivariable logistic regression models were used to analyze the data. Nepalese students were less likely to know where to receive HIV testing in Japan than Chinese students (AOR = 0.12, 95% CI 0.01–0.96). Students who did not need Japanese language interpreters during visits to health facilities were more likely to know where to receive HIV testing (AOR = 1.93, 95% CI 1.14–3.25). Students who did not have knowledge of free and anonymous HIV testing in Japan were also less likely to know where to receive HIV testing in Japan (AOR = 0.18, 95% CI 0.08–0.42). Students who did not have knowledge of free and anonymous HIV testing (OR = 0.05, 95% CI 0.02–0.10) and who had not utilized HIV testing in their home country (OR = 0.12, 95% CI 0.06–0.27) were less likely to utilize HIV testing in Japan. Factors associated with access to HIV testing among Japanese language school students in Tokyo are nationality, need for Japanese language interpreters, perceived access to doctors/health workers, utilization of HIV testing in the home country, and knowledge of free and anonymous HIV testing. These findings may help to design interventions for improving access to HIV testing among international students in Japan.