Contemporary young college students are the vital force to promote social development and progress and the main force of network application, and they are the important force to maintain the national network ideological security, and the construction of their ideological security is crucial. Aiming at the risk of network public opinion existing in the new media environment, this paper explores the main influencing factors affecting the evolution of network public opinion through the complex network public opinion evolution model and the viral propagation model, on the basis of which it designs five effective strategies to control the risk of college students’ network public opinion, and proposes the path of constructing college students’ network security ideology. The results of the study show that public opinion will develop in a certain direction and converge to a certain state in the process of information dissemination, and the smaller the absolute value of the difference between the proportions of positive and negative tendencies in the group |p+ − p−|, and the closer the proportion of the number of viewpoints u+ is to 0.5, which indicates that the more controversial the topic is, the more difficult it is for the group to reach a unanimous agreement. The average node degree 〈k〉 of the scale-free network of the BA is able to effectively influence the individual’s speaking enthusiasm, and the larger the 〈k〉 is, the the faster the information spreads, and the wider the final spread will be. At the same time, when the nodes of the initial discussion group have a higher degree, the scope of information dissemination can be greatly improved. Among the five risk control strategies for college students’ online public opinion proposed in this paper, the control method based on group influence is better than the other four control strategies, and the control effect is more significant, which can quickly block the way of public opinion dissemination and effectively inhibit public opinion dissemination.