The ability of computational thinking is the ability needed to balance the development in the 21st century digitalization era. The purpose of this study was to describe the ability of students' computational thinking in solving open ended HOTS problems in terms of reflective and impulsive cognitive styles. This research is a descriptive research with qualitative approach with the research subjects are four students of class VIII SMP Muhammadiyah 1 Sumberpucung, namely two students with reflective cognitive style and two students with impulsive cognitive style. The results of this study found that the ability of computational thinking students with reflective cognitive style is in the high category while students with impulsive cognitive style in the medium category. R1 can fulfill the aspects of decomposition, pattern recognition, abstraction, and algorithm design but the solution obtained is not correct because it is less careful when working. R2 also fulfills all four aspects and the solution obtained is correct. I1 and I2 both could not fulfill the algorithm design aspect, but could fulfill the aspects of decomposition, pattern recognition, and abstraction even though they were still less precise
