This study aims to determine the scientific thinking ability of the eleventh-grade science students at the school of the coastal area of ​​Bantul Regency, Special Region of Yogyakarta. The study is a descriptive quantitative. The population of this study is all the public schools in coastal areas. Subjects were 52 students of class XI IPA at SMAN 1 Srandakan and SMA Negeri 1 Kretek. Sample acquisition technique is cluster sampling methode. Scientific thinking skills of students measured using a test instrument consisting of 25 multiple choice questions containing four aspects of scientific thinking, namely: (1) aspects of inquiry; (2) aspects of analysis; (3) aspects of inference; and (4) the aspect of argumentation. The data obtained were tested using descriptive statistics. The results showed low student scientific thinking skills. Percentage of scientific thinking skills of students in every aspect is as follows: aspects of inquiry 19%; aspects of analysis 17%; aspects of  inference 15%; and aspects of argumentation 7%. These percentages indicate scientific thinking skills of students in all aspects less than 20%. It can be concluded students' scientific thinking ability is low. Low percentage of scientific thinking generally because of student's ability which is not used to be trained to think scientifically in learning. Training of scientific thinking in learning can be applied by implementing learning models that train students to be able to find out knowledge such as researchers doing the research process through the model of learning-based investigation.