In view of the severe employment situation of college students, and the questions on imperfection of college training system and employment mechanism, external environment interference and internal competitiveness deficiency of students, and post distribution and employers' influences, this paper takes science and engineering college students majoring in water conservancy as an example to explore a multilateral joint action training mechanism. To strengthen the employment security ability, colleges and teachers should be taken as important guarantee, students as main body, and the parents, society and employers as external driving forces, to scientifically formulate training programs and measures.