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Crack frequency and strength of rock is one of the most important factors for geotechnical evaluation of rock for dam design and construction. As for rock crack frequency, RQD is very popular index and usually measured for boring core, it is seldom measured in adit or natural outcrop. As for rock strength, unconfined compressive strength and degree of repulsion of Schmidt Rock Hammer is brief and useful index. However, measurement of the former is rather expensive and that of the latter can not be performed in borehole. Therefore, the very important factor, crack frequency and strength of rock, is not systematically integrated for dam design and construction. In this paper, MRCI and Shock Response value is found to be useful index of crack frequency and strength of rock, respectively, by comparing with Rock Class in adits and in boreholes of a dam site in Northern Hokkaido, Japan, of which geology is Neogene andesite and peperite. Result of adit is shown in Fig. 1. Each Rock Class is well separated by the two indices. When MRCI is more than 15 cm and SR-Value is more than 35 m/s², rock is classified into CH Class. When MRCI is less than 7 cm or SR-Value is less than 20 m/s², rock is classified into CL Class. When rock condition is between CH and CL Class, rock is classified into CM Class. These classification criteria are also found to be applicable for boring data without lessening the accuracy so much. Therefore, rock evaluation in both borhole and in adit is briefly and objectively integrated by measuring these two indices.