Coding education has been offered to primary school students due to certain reasons: (1) coding improves students' problem solving and creative thinking skills; and (2) it has high visual-quality and easy-to-use block-based tools. In this study, the effects of coding education on 4th grade students' self-efficacy and scratch coding achievement were examined. The study used a single group pretest-posttest weekly experimental design. The participants consist of 60 students studying in two classes of a primary school located in a small district city of Turkey. Self-efficacy scale and Scratch coding achievement test were used as data collection tools. Following the pre-test applications, coding training was given with the Scratch program for three weeks, and then post-test applications were carried out. In order to examine the effects of the training on students' self-efficacy and scratch coding achievement, dependent samples t-tests were conducted. The results showed that this training significantly affected students' self-efficacy and Scratch coding achievement.