This study was conducted in order to develop a valid and reliable scale that can be used in measuring self-efficacy of candidate music teachers in rendering piano education to children of 6-12 years. To this end, a pool of 51 items was created by using the literature, and taking the opinions of piano professors and piano instructors working with this very age group through open ended questions. This measurement tool was applied to a sample of 260 students in 1st, 2nd, 3rd and 4th grades in music education in fine arts divisions, Mehmet AkifErsoy University, Adnan Menderes University, Pamukkale University and Balikesir University, Turkey. An explanatory factor analysis was conducted to determine the construct validity under the validity and reliability study of the self-efficacy scale in rendering piano education to children of 6-12 years. According to the explanatory factor analysis, the scale was composed of four sub-dimensions that explain 49.08% of the total variance. Reliability analysis was conducted by calculating the test item-total correlation, Cronbach Alpha internal consistency coefficient and Spearman Brown two-half test correlation; Cronbach Alpha coefficient was found as 0.947 and the two-half test correlation as 0.851 for the entire scale in general. Under the findings of this study, we can suggest that this scale is a valid and reliable measurement tool in determining self-efficacy of candidate music teachers in rendering piano education to children at the age group of 6-12.