The purpose of the study was to explore how contents related to sustainable development were presented in Japanese, Korean, and Singaporean elementary mathematics textbooks. For this purpose, the contents in the textbooks were analyzed at both macro and micro levels through a mixed method research. The results showed that the sustainability-related contents were included from the third or fourth grade in all the textbooks. The related contents were involved to mathematics content domains of Numbers and Operations, Pattern, and Data and Possibilities. The sustainability-related contents were used both to introduce and to apply mathematical concepts or principles. Most of the sustainable development activities led students to solve problems by using the mathematical contents they had learned, while some other activities induced students to consider sustainability as well as to solve problems. This study is expected to give implications for textbook developers and teachers to connect sustainable development meaningfully to elementary mathematics education.