According to theory of investment portfolio,the target of needy university students is to achieve career income maximum.They in pursuit of income maximum base on same risk or risk minimum base on same income.So it needs to associate with their choose career behavior when discussing career profit and risk of needy university students.This thesis tries to create a model and combine the survey of 539 needy university students who from four Xiamen high school to have the research.The result of research shows these three factors bring significant effect to expectative career profit: career risk cost,need factor,expectative income in future.Need will not affect the students' confidence when they are applying for a job,but it will make their mentality to be more worrying so that increase relative risk when they obtain employment.Reasonable salary preference makes for high profit career.Vocational guidance is the efficiency method which helps needy university students to disperse career risk and achieve the career profit maximum.Major success and major satisfaction are the important factors of future career expectative profit and risk.It helps to increase expectative profit if the career matches with the major.