The purpose of this study is to investigate the correlative causality of college students' belief to consuming network rumors. ”Source credibility,” ”affection” and ”involvement” are operated as the main variable effects on college students' belief to these rumors. By using ”involvement” as a moderator, this study analyzes its correlation with the other factors. This study is designed to awake college students' attention to network messages, and to provide suggestions for the enterprises. The findings of this study include: 1. both source credibility and involvement have positive effects on the college students' belief to consuming network rumors; 2. affection has part of effect on the college students' belief to consuming network rumors, but with no causal relation; and 3. both source credibility and involvement have positive effects on the college students' belief to consuming network rumors under different involvements.