Karst rocky desertification is an eco-geo-environmental problem which has been paid more and more attentions in recent years. After considering the philosophical evidence, we discussed the connotation of karst rocky desertification to a more comprehensive and reasonable extent in virtue of introducing the background，in which all kinds of connotation were put forward，analyzed and compared connotations of karst rocky desertification. Karst rocky desertification is a process of land devolution that mainly occurred at the background of tropical，subtropical belt and warm temperature zone vegetation is destroyed，its main phenomena can be summarized as followings:eroded seriously, bedrock and gravels are exposed，the land productivity declines seriously, and at last the karst succeed to desert liked landscapes under human activities and natural forces on the vulnerable environment of ecology and geology, and karst rocky desertification are influenced by interactivities of human beings and the vulnerable environment，its essence and diagnostic sym- bols are land productivity degradation and landscapes appear to be karst rocky desertification respectively.