In modern society，the youths participating in various social affairs have been popular，which matches social development. Comparing changes in sense of participation and participative behavior at different eras，the youths are provided with obvious characteristics of the times，such as positive attitude of political expression and strong desire for politics. As political sense of the youth is improved day by day，their willingness and motivation to participate in social organizations are strong and multiple. Nevertheless，development of new technology has changed current pattern of the youths participating in political affairs. Social organizations of all kinds flourish rapidly，but gap between expectation and reality of voluntary service still exists. Therefore，against the background of new age，we must strive to explore social participation mechanism of the youths and further expand positive influences of their participation in society.