Based on a 530 sample size survey in the Guangzhou High Education Mega Center on the 2008 Tibet Issue, the direct and indirect effects of personal factors, i.e. perceived online news believability, interpersonal communication, and political interest, on the issue cognition are tested using SEM approach. Mediation analyses based on bootstrapping method indicate that the “self-perceived knowledge” (of the issue/event) is an effective mediator between the personal factors and the issue cognition; Especially, between interpersonal communication, political interest and the issue cognition, the mediation effect of “self-perceived knowledge” is not only significant statistically, but also significant practically.