It discusses the feasibility and concrete methods of using function game with more digital characteristics as external publicity in the digital age. Combined with the current situation of college enrollment publicity, the educational value of games is gradually elaborated by means of actual cases, and the characteristics and development trend of function game are further analyzed, as well as the ways to play the advantages in college publicity. In order to enrich the content and form of external publicity of Southwest Jiaotong University and improve the competitiveness of high-quality students, the student team designs a function game named "Looking for MAO Yisheng" based on the SGDA framework. The game is themed around recalling and commemorating Mr. Mao, and cleverly achieves external promotion of the university, disciplines, professional strength, and characteristics through campus exploration. Function game is an emerging carrier in college enrollment publicity. It has the advantages of high transmission efficiency, wide scope, flexible content and interactivity. With other traditional enrollment publicity channels, it could bring better publicity effects to universities.