In this study, 109 chemical compositions of clinopyroxene (Cpx) megacrysts were collected from Cenozoic basalts in eastern China. The main characteristics of the. occurrence, physical properties and mineralogical chemistry of the Cpx megacrysts are studied 1 liy. means of large amounts of calculations and projec- tions. The authors present in this paper their own views on the genetic informa- tion of Cpx megacrysts. The compositions of megacrysts were characterized by higher contents of Al2O3 and Al(v1) and moderate Ti and Mg'. But in the "reaction rim" the contents of A1203 Na20, A1 and Al(v1) obviously decreased. The main species of Cpx megac- rysts is augite, while diopside, salite and endiapside are rare. And, the composi- tions of Cpx megacrysts are somewhat varied in .different regions of China.In southern China，the content of Wo' is relatively high with lower A1203; in the north, .Es and Al2O3 are higher; while in the northeast En is higher with mode- rate A1203. The opinions of the authors concerning the genetic information of Cpx me- gacrysts are; 1. The Cpx megacrysts are the products of crystallization of the host basal- tic magma in the upper mantle, but not xenocrystals derived from mantle disin- tegration. 2. The crystallization temperature and pressure of CpX megacrysts in China are 1021-1209℃and 1.4-3.2 Gpa respectively. Therefore the depths of Cpx me- gacrysts crystallization are approximately 48-104 km. The depth is shallower in southern China,deeper in northeastern China and deepest in northern China. The "reaction rim" was formed. at amore shallower mantle`=crust depth. 3. The Cenozoic basalts in eastern China all occur within the continental plate, dominated by alkalibasalts,with little tholeiite the basalts in areas along the basalts, since regions are close marginal sea.