Ideological function is the core of the basic research on ideology. Ideological function is a new perspective to promote the construction of socialist ideology in China. In the study of ideological function, regardless of the historical background and specific practice, it is easy to “blur” the study of ideological function, resulting in empty understanding of ideological function. Based on the historical orientation of the new era, and combining Xi Jinping thought on socialism with Chinese characteristics, this paper demonstrates the relevant functions of socialist ideology in the political, economic, cultural, social and diplomatic fields. Under the circumstances of marketization, “microera” and globalization, we hope to truly improve the function of socialist ideology by leading the reform direction of socialist market economy, purifying cyberspace and competing for the right of international discourse.