This research aims to describe students' critical thinking ability based on the level academic and gender. The populations of this study were 132 students participating in five classes of Calculus course. The research data obtained through technical tests and interview techniques. This study found that the high level of capability, both male students or female students already have the ability to generalize the ability to complete the data provided and do not yet have the ability to identify and justify the concept and analyze algorithms. At medium and low levels of capability, male students or female students show similar.