Attribution of risk is one of the crucial new media accountability to the society. Based on the content analysis of news coverage in January 2013 on the Renmin Website （People. cn），which is the most prestigious news website in mainland China，in terms of severe haze and fog weather condition，this paper elaborated the new media’s motivation of risk attribution and the accountability framing strategies，to explore how the new media fulfill its social responsibility during the process of risk discourse production. This study suggest that the source is one of the key parameter for new media to construct the risk discourse system，and the media preference to certain sources would have effect on the three dimensions of news media attribution motivation，and further to influence the attribution objects. The findings indicate that the attribution motivation of Renmin Website tends to avoid attributing the air pollution risk to any concrete actor and obscuring the divergences of risk discourses from various agents，and the subtle strategies of attribution framing of the Renmin Website，may cause the “collective irresponsibility” of the society in the course of handling risks.