Pyroclastic rocks are a kind of transitional and complex rocks between lavas and sedimentary rocks. Petrologists,both at home and abroad have spent a lot of time on the classification of pyroclastic rocks, and suc_cessively put forward the classification of pyroclasts, the petrographic and the petrogenetic classification of pyroclasic rocks. Widely accepted as they are, the classification of pyroclasts and the petrographic classification of pyroclastic rocks stipulated by the IUGS Subcommission on the Systematics of Igneous Rocks fail to consider the classification with Chinese characteristics, which was put forward in 1950s to 1960s and improved in 1980s to 1990s and has since been widely used in China. On the basis of the past schemes, new classifications of pyroclasts and the petrographic as well as the petrogenetic classification of pyroclastic rocks are proposed in this paper. Volcanic sedimentation is a frontier realm between volcanology and sedimentology. The past twenty years have witnessed great development in the study of volcanic sedimentation, both theoretical and methodological. The dynamics, experimentation and simulation of volcanic eruption and sedimentation have become the main trend in the future. Despite of this, the field geology and the character of pyroclastic rocks remain the basis of the petrogenesis of pyroclasic rocks.