PURPOSE: To prevent the deflection of an edge part at tension time and to enable more precise cutting by arranging a lot of holes at the waist part abutting on a drum in a band saw for cutting an endless continuous hard body.

CONSTITUTION: A belt like plate 1 consisting of a thin steel plate and formed in an endless and continuous shape in continuation annularly is formed with an edge part 2 providing slits 7 at equal intervals and made by arranging a tip 6 which contains diamond abrasive grains between tips on one side end part thereof. A lot of holes 4 are formed by press work on the waist part 3 between a back part 5 which is the other side end part of the belt like plate 1 and the edge part 2, namely the abutment part on the drum 8 of the belt bar plate 1. The generation of the deflection of the edge part 2 is thus prevented and precise cutting is enabled. Also the numerous holes 4 reduce the weight of the belt bar plate 1, prevent the slippage with the drum 8 as well and yet the circulation of air, a cutting oil or coolant, etc., is improved and so the heating by cutting can be prevented.