Abstract:Mao Zedong Thought on Investigation and Research is an important part of Mao Zedong Thought, which has gone through the five stages of incubation, germination, formation, maturity and deepened development. In the process of development, Mao Zedong systematically expounded on the important role, main purpose, fundamental principles, scientific methods and basic attitude of investigation and research, which have been gradually developed into a scientific system of Mao Zedong Thought on Investigation and Research, creatively developing the methodological system of Marxism. At the critical juncture of achieving the second centenary goal, it is of great significance to conduct studies on Mao Zedong Thought on Investigation and Research for accurately grasping the party’s situation, national conditions and world situation, and driving the socialist cause in China to make breakthrough progress.