Based on the deep understanding and comprehension of comrade Xi Jinxing’s important remarks on literary and art work，this article points out that the series of General Secretary Xi’s speeches scientifically and systematically answer the important theoretical and practical questions during the new era of literary and art development，including function theory，essence theory，fine art theory，efficiency theory，innovation theory，criticism theory，talents theory，and leadership theory. It is the latest achievement of socialism literary theory with Chinese characteristics and marks that out Party has achieved a new height of the understanding of the socialism literary law with Chinese characteristics，and it is also a scientific guideline in literary and art field in the aspects of unifying thinking，guiding practice and promoting work. <<