Athletes of all ages report using imagery extensively to enhance their sport performance. The Sport Imagery Questionnaire (Hall, Mack, Paivio, & Hausenblas, 1998) was developed to assess cognitive and motivational imagery used by adult athletes. No such instrument currently exists to measure the use of imagery by young athletes. The aim of the present research was to modify the Sport Imagery Questionnaire for use with children aged 7-14 years. This was accomplished through three phases. Across these phases, evidence was generated showing adequate factorial, convergent, and discriminant validity and reliability of the instrument, which is termed the Sport Imagery Questionnaire-Children's Version. In addition, the relationships of scores on the Sport Imagery Questionnaire-Children's Version to gender and age were examined. While it was found that male and female athletes employed imagery to about the same extent, there were some age group differences in the use of imagery. (Contains 5 tables.)