This cross-sectional study aimed to examine factors associated with Japanese undergraduate nursing students' motivations and needs to study English. An online survey at one university in Tokyo was conducted from July to October 2018. This survey included students' basic interest in and reasons for learning English, attitude toward communicating with non-Japanese people, willingness to study English, which could be related to motivations and needs to study English. Structural equation modeling was used to map the association among variables. Overall, 167 students completed the survey. The most frequently cited motivation and needs to study English were for "daily use," such as traveling. Participation in a study tour through the university was associated with willingness to study English, which was associated with both motivation and needs. Improving curriculum and systems is necessary so that students realize the necessity of English in their clinical or professional activities, and find willingness to study English.