Based on the analysis of the relationship between the indentation hardness and the rock destruction specific energy, it is concluded that the specific energy gives a more comprehensive indicator of rock destruction difficulty To simplify the measurement of the specific energy,a specific energy estimation method based on the indentation hardness, plastic co efficient and volumeric expansion rate of the indented crater is put forward with the calculation formulae of the specific energy derived, and a comparison is made between the calculation values and the actual measurements, which indicates some practicality