The purpose of this study was to develop "The Scale of Determining Self-Directed Learning Implementing Skills" for primary school students. Data were gathered by a survey method. In order to develop this scale, draft items was developed through a literature survey (tarama), observations and interviews done with teachers, parents and students, and presented to experts for evaluation. After alterations based on experts' suggestions, a pilot study with 16 primary students was held to revise the items. After the revision the scale was administered to a sample of 500 3rd and 4th primary school students. In order to determine the validity, exploratory and confirmatory factor analysis was performed. As result of the analyzing data, The Self-Directed Learning Implementation Skills Scale which had 45 items contained five factors and these factors explained %48.01 of total variance. The five factors were named as "Inquiry Skills" (alpha=.90), "Thinking Skills" (alpha=.86), "Using Strategies Skills" (alpha=.79), "Evaluation Skills" (alpha=.81) and "Collaborative Learning with Peers Skills" (alpha=.73). The overall internal reliability coefficient (Cronbach Alpha) of the scale was found as .95.