Cognition refers to the processing of information, applying knowledge, and changing preferences.Cognitive style or “thinking style” is a term used in cognitive psychology to describe the way individuals think, perceive and remember information. Cognitive style differs from cognitive ability (or level), the latter being measured by aptitude tests or so-called intelligence tests.Cognitive style is the manner by which individuals perceive information in the environment and the patterns of thought that they use to develop knowledge base about the world around them.In the present study the investigators intended to find out and compare the Cognitive Style of under Graduate Male and Female Mathematics Students. The sample of this research consists of 240 out of which 120 Male and 120 Female under Graduate Mathematics Students from Coimbatore District. The investigators used Cognitive style Inventorydeveloped and standardized by Lorna P. Martin, (1983). Thus the collected data were analyzed using descriptive statistics and ‘t-Test’ to find the Mean score difference in the Cognitive Style between male and female Undergraduate Mathematics students and the findings show that there is a significant difference in the level of Cognitive Style between male and female Undergraduate Mathematics students. But, there is no significant mean score difference in the Cognitive Style between male and female Undergraduate Mathematics students.Hence, it is concluded that sex does not influence cognitive style of undergraduate mathematics students. Keywords: Cognitive style, Cognitive abilities, Intuitive and systematic styles, Cognition psychology and functions of brain.