Diamond drilling is one of the main drilling methods in China. It is applied widely in geological explotation， and oil and gas drilling. In order to improve technical and economical index of the method， research on the stress-strain state of rock to be drilled， the rock fragmentation process and its relationship with drilling parameters is very necessary. Russian drillers have done a lot of relevantwork： they studied the optimal relationship between penetration rate and drilling parameters， proposed the concept about the combination of critical drilling parameters， and recommented measures guaranteeing normal drilling and prevening abnormal wear of drill bits， etc.， which can provide some reference for the Chinese counterparts.