The aim of this study is to examine the effect of robotic design with Arduino on students' attitudes towards programming and on their perceptions of self-efficacy in programming. The study group consisted of 25 sophomore students attending the Department of Computer Education and Instructional Technologies in a state university located in the south of Turkey. The study lasted 12 weeks and the participants performed robotic design activities with Arduino throughout the process. Firstly, participants prepared a prototype and then programmed it for 8 weeks, and they created their own designs in the remaining 4 weeks. The Computer Programming Attitude Scale and Computer Programming Self-Efficacy Scale were utilized as the data collection tools in this pretest-posttest experimental study. The findings revealed that robotic design activities with Arduino significantly improved the participants' attitudes towards programming and programming self-efficacy. In addition, according to the participants' views, the factors that cause this improvement can be listed as activities' being enjoyable, facilitating and concretizing the process, being interesting and practical. Moreover, these robotic design activities were found to contribute to students' understanding of finding bugs and the logic of programming.