The aim of this study was to develop a psychometric scale that aims to measure self-directed learning skills of undergraduate students. The literature was first reviewed, and a conceptual framework was established to identify the basic characteristics of the scale. In addition, similar scale development studies in and outside Turkish literature were examined. After then, criteria were execute which related scale and a 72-item pool was formed, and it was revised in line with expert views, and a version with remaining 53item was implemented on 753 students attending Hacettepe and Baskent Universities. The data were implemented exploratory factor analysis. It was found that the scale consisted of four sub-scales (motivation, self-control, self-monitoring and self-confidence), and twenty one items associated with the sub-scales. Also, in order to determine the construct validity of the scale, a confirmatory factor analysis was carried out with 2600 students attending Hacettepe and Baskent Universities. This second group of students were the first and last year of students in the common programs in both universities. The fit indices of the scale showed good or acceptable values. According to this, the 21-item and four-factor structure of the 'Self-Directed Learning Skills Scale' was confirmed as a model. The Cronbach Alpha internal consistency coefficient was, 895. As a result, it was concluded that the "Self-directed Learning Skills Scale" was a valid measurement tool and produced reliable scores for measuring self-directed learning skills.