After operation and revision for years, although the existing construction and management measures for off-campus internship bases made some achievements in cultivation of application-orientated talents, there are still some problems such as insufficient quantity of internship base engineering projects, engineering corporations and first-tier engineers’ low enthusiasm in participating in cultivation of college and university talents, professional teachers’ insufficient motivation in participating in internship and base construction and poor hardware conditions in the internship base. Based on the existing problems in the internship base construction and management mode, through analyzing the interrelations among colleges and universities which are the internship plan makers, internship bases which are the significant participants and the interns which are the principal beneficiaries, we put forward the “trinity” construction and management mode from the angle of improving the internship quality and effect.