Abstract: Marxist dialectics that Marxist classic writer founded, stuck to and developed, is coincident with Marxist spirit.It has three gradations including dialectics, dDialectics of nature and materialistic dialectics, which can provide the important guidance of world outlook and methodology for constructing the socialistic harmonious society.At present, domestic academic circles emphasize one-sidedly the natural science instead of the social science, emphasize one-sidedly the applied research instead of the fundamental research, emphasize accord instead of contradiction, conflict, dialectics, and even emphasize philosophy of scientific technology instead of natural dialectics, and so on.These phenomena, that are disadvantageous for constructing the harmonious society, going against Marxist dialectics in nature, should be corrected.