Abstract: This article first established a polynomial regression model based on a large sample network questionnaire survey, and then discussed the structure and characteristics of online political participant of China from the following four aspects: demographic characteristics, basic characteristics of using network, characteristics of online political participative behavior and attitude about the effect of online political participation. It is found that these four aspects have the following characteristics respectively. The online political participants are mainly consisted of those rational youth who have highly educated background, high incomes and high comprehensive quality. The occupational prestige in the realistic society does not match with the network voice, sometimes it even means the least network voice. Social media has become the main tool and platform for online political participation, especially microblogs which play a unique role in online rights protection. The main goal of civic online political participation is self-actualization.