In this article we consider the problems of "critical thinking"as a cause of insufficient development of soft skills in high school students. In the course of theoretical analysis the concept and characteristics of critical thinking as a soft skill are established and different approaches to the development of critical thinking skills in high school students are outlined. Since critical thinking allows to guide and control the whole process of learning in school, including the independent development of students regarding the acquisition of not only knowledge, but also soft skills. The special connection between logic and creative thinking is noted. The main ways of developing critical thinking as a factor in the development of soft skills according to the Delphi model (Peter Facione) are outlined. The results of practical research based on the key cognitive skills have shown that the level of development of soft critical thinking skills is a necessary condition for the development of high school students, as soft critical thinking skills were developed in them during the experiment, albeit slightly (due to the use of modern techniques and methods of technology in the process of teaching and education), which determines the effectiveness of their further development. It is recommended to use in school education, in high schools, interactive techniques and methods of developing soft skills, while taking into account the age of students and their need to form critical thinking both for self-development and for the acquisition of other competencies.