The development changes and the epidemic situation in the century have caused great and profound changes of the times，which continue to affect the development of Chinese media. New media is embedded into people’s daily life in the form of deep media，and the construction of new media’s social responsibility has become the internal requirement of new media’s sustainable development. On the whole，the performance of social responsibility of new media in 2021-2022 is above the middle level，with the average total score of 3.180505 and the scoring rate of 63.61%. Compared with the evaluation results of the 2020-2021 cycle，the scoring rate has decreased by about 5%. Specifically，the scoring rates of the four first level indicators from high to low are information production（76.39%），coordination and communication（55.71%），value guidance（50.54%）and culture andeducation（42.43%）. With the evolution of the new media responsibility fulfillment scene from intermediary to platform，the new media social responsibility fulfillment has created a new reality dilemma：the platform monopoly characteristics confront social rules，the platform intervention characteristics challenge public interests，and the platform bilateral characteristics eliminate the subject’s rights and responsibilities. It is urgent for the academic community to transcend the disciplinary barriers of social responsibility theory and further clarify the new situation of social responsibility of new media in the context of platform. Taking attributes as the key link and elements as the goal，this study constructs a new framework with the core dimensions of subject matrix，degree hierarchy，content diversification and mechanism coordination，in response to the new era test and social expectations of new media social responsibility.