The purpose of this study was to investigate the mathematical experience while children roleplay in a spaceship and a fruit-store. The subjects were the children involved in the roleplaying area during their free-choice activity period. The kindergarten was located in Seoul, Korea and the class consisted of 15 five-year-olds. Data was collected three times a week for four weeks. Role-playing happened during the free-choice activity and it took about 50-60 minutes each time. I collected the data in three different ways: field notes, audio recordings, and video recordings. Data was analyzed according to five mathematical concepts: number and operation, space and shape, measurement, pattern and data analysis and probability. Based on the results of this study, children mainly experienced and developed mathematical concepts of ‘number and operation’, ‘space and shape’ and ‘measurement’ while role-playing in a spaceship and a fruit store.