Abstract: This paper introduces the sampling method, main research contents and applicable conditions of cement clinker petrographic analysis. Petrographic analysis of cement clinker directly uses optical microscope to observe the mineral morphology, size, distribution and harmful components in clinker, understand raw material ingredients, raw meal fineness, clinker calcination and cooling, understand the calcination atmosphere in the kiln, observe the morphology of magnesium oxide in clinker, there are many factors affecting the lithofacies structure, which need to be analyzed in combination with the actual production. In the actual production, vertical analysis should be adopted as far as possible in lithofacies analysis, which has greater guiding significance for production.