The aim of this paper is to present and analyze the data collected from a quantitative international study of the differences between Japanese and Korean request discourses. Between November 2018 and January 2019, Japanese and Korean university students (358 and 377 individuals, respectively) were asked to complete a survey. The questionnaire employed was designed to verify the findings of a previous qualitative study, conducted using an introspective method, in which the authors examined their own discursive practices and drew on their intuitive understanding of their respective native cultures. The research is based on synchronous discourse theory, which focuses on social culture, attitudes, the contents and the expressions of language and the interrelation between these four aspects. Results of the analysis are as follows. There were no significant differences between the circles of acquaintance. 95% or more of both the Japanese and Korean students had close friends. On the other hand, the differences in contact frequency were clearly significant. While more than 60% of the Japanese respondents answered that they contacted close friends only when they had a reason to do so, more than 80% of the Koreans contacted close friends frequently even when they had nothing in particular that they needed to convey. Such socio-cultural differences also influenced the way the respondents thought as well as the contents and expressions of their discourse. Fewer than 50% of the Japanese students agreed that ‘expressing oneself clearly is polite’, whereas more than 90% of the Koreans agreed with this statement. This result shows that politeness is not universal. More than 70% of the Japanese respondents answered that, when asking to borrow something of little value from a close friend, they would explain why they needed to make the request. On the other hand, more than 50% of the Koreans thought no explanation was necessary in this situation, and more than 40% answered that a detailed explanation was unnecessary. The Japanese students indicated that, when an invitation to the movies was declined with the expression “I’m sorry”, they would feel satisfied that they had understood the reasons for the refusal. More than 70% of the Koreans, however, stated that while they would feel that they had understood, they would still prefer some explanation of the reasons that led to the invitation being declined. These results confirm the findings of previous qualitative research undertaken by the authors.