PURPOSE: To make sufficient cooling and lubrication achievable from the initial stage of cutting and waste water preventable.

CONSTITUTION: In this wire saw method, two through holes 2, 2a are installed in both upper and lower ends of a vertical cutting slated line of a wall concrete structure 1, and a sealing part 3 is formed along the cutting slated line at the backside of the structure 1 inclusive of these through holes 2, 2a. In this sealing part 3, a pipe 3a is set up along the cutting slated line, and it is formed after sticking the pipe 3a so as to be embedded by a bonding agent 3b. Next, a front sealing part 4 is set up in a front side of the structure 1. This sealing part 4 is provided with a pair of guide plates 4a and a pair of flexible sealing plate 4c to be locked along the front side cutting slated line of the structure 1. In succession, a wire saw 5 is inserted into the pipe 3a, and a driving pulley 6b of a driver 6 is rotated and driven, whereby the wire saw 5 is circulatively traveled as giving the specified tension to it. At this time, cooling water is fed out of a delivery side of the wire saw 5 via a hose 7.