The problem of network security is increasingly evident in China, the main reason lies with the lack of network security awareness among the public as well as the substantial gap between the cultivation of the Internet security talents and the real social demand for talents. However, in recent years, colleges and universities have started to conduct large class enrollment, involving deepening reform in various aspects like talents cultivation modes, teaching methods. Against this background, this paper constructs a multidirectional cultivation system for network security talents 'practical abilities from multi-dimensions including career development, public security awareness. It also integrates the characteristics of the reform of large class enrollment with the target of meeting the real social demand for network security talents. In the system, during comprehensive education phase, students increase their network security awareness via practical activities, while during specialized education phase, students improve their practical engineering abilities via the integration of curriculum systems, scientific activities and practical activities based on working scenarios. In addition, it could substantially ensure an improvement of the practical teaching level of undergraduates through revising its teaching contents based on the evaluation and feedback system. [ABSTRACT FROM AUTHOR]