This study aimed to elicit middle school pre-service mathematics teachers’ personal meanings of realistic mathematics problems. The study presents a portion of a larger design-based study involving teacher training sessions encompassing small-group discussions, writing realistic mathematics problems, and whole-group discussions. The audio records of the pre-service teachers’ discussions and their written artifacts were analyzed in three coding cycles. The findings indicated that the pre-service teachers’ personal meanings of realistic mathematics problems comprised both in-school situations that students themselves could experience and real-life situations that mostly required occupational decisions such as optimization in engineering. Besides, pre-service teachers considered that realistic situations often involve multiple information and could be solved by multiple solution methods that might lead to multiple acceptable answers. This study highlighted the informative role of articulating pre-service mathematics teachers’ personal meanings of realistic mathematics problems in designing teacher education courses and further discussed such implications for mathematics teacher education.