Abstract: Based on the grounded theory,this paper encodes the official website data of MIT,the University of Chicago,the University of California Berkeley,the University of Pennsylvania,Cornell University and the University of California San Diego,and analyzes the system of diversified professional capacity for doctoral students at first-class universities in the United States,including high-standard target training objectives to match the needs of the labour market,multi-dimensional guarantee mechanisms based on the relationship network,whole process of vocational guidance based on self-reflection and all-round vocational skills training that is both academic and practical.Our universities needs to take up the main responsibility of training doctoral students,face up to the trend of diversified career choices for doctoral students to meet the needs of society,strengthen systematic thinking,create a community for the cultivation of doctoral students diversified professional capacity,and collaborate with stakeholders to strengthen the construction of a multi-channel and enhanced training system for academic doctoral students.

Key words: American first-class universities, doctoral training, professional capacity, grounded theory