The purpose of this study was to calculate the ratios between energy consumption and the following two variables; mechanical power exerted to the oar and to the boat shell. A third ratio between mechanical power exerted to the oar and the mechanical power exerted to the boat shell was also calculated. The subjects of the study were 64 male oarsmen; 8 crews of eight, (mean performance 6'20" ranged from 6'04" to 6'35") including a Japanese champion crew in 1985. The energy consumption (EC) and mechanical power exerted to oar by oarsman (P_o) were measured using n rowing tank in which water was circulated at 3.2m・s^<-1> by motor driven pump. The subject were requested to row for 6 minutes with maximum effort in the rowing tank. EC was estimated by averaging the Vo_2 during 4 minutes to 6 minutes period from the beginning of the rowing exercise. P_o was calculated from the force applied to the oarlock pin and its angular displacement in all strokes during 6 minutes of maximum effort rowing. The progressive power of the shell (P_s) was estimated from the mean velocity of the boat over 2,000 meters and the total boat mass including all oarsmen, coxswain, and rowing apparatus using a equation introduced by Secher and Vaage (1980). EC, F_o, and P_s of a crew were obtained by averaging the values of 8 oarsmen in EC, P_o, P_s, respectively. Performance time was related significantly to the following ratios, P_s/P_o, P_s/EC, and P_o/EC. From these results, it was suggested that the better skilled crews are consisted of those individuals with similar rowing patterns, and are able to better transfer the force exerted to the oar by the oarsmen to the shell. A crew with a higher mechanical efficiency will obtain a more successful performance,and those ratios reflect as the important factors on successful rowing performance.