Discrete mathematics is the basic mathematics of computer science. Taking discrete quantity as the research object, this paper describes the characteristics of discrete computer science gradually established with the development of computer science. Previously scattered in various branches of mathematics, such as set theory, graph theory, mathematical logic, algebraic structure and so on. Mathematical modeling is a way of thinking. Three years in college and one year's work. I feel that cultivating thinking ability is very useful and comprehensive. Students who are very academic and come out through communication.