The invention relates to a board sawing machine, in particular to a full-automatic multi-positioning high-speed board sawing machine, and mainly solves the technical problems of imprecise board positioning, incapability of calibrating and positioning boards with different sizes before sawing and low sawing precision caused by easy shaking of the boards during sawing in a board sawing machine in the prior art. The full-automatic multi-positioning high-speed board sawing machine comprises a machine body; a pair of stand columns is arranged at the front end of the machine body; a cross beam is arranged on the stand columns, and is integrated with the stand columns; a Y-axis rail is arranged on the cross beam, and is slidingly connected with a saddle; the saddle is connected with a Y-axis feedservo motor through a lead screw; the saddle is slidingly connected with a ram; a Z-axis feed servo motor is arranged at the upper part of the ram; a power box is arranged at the lower part of the ram, and is respectively connected with a main shaft motor and a saw blade; a reference clamp device and a clamping clamp device are respectively arranged on two sides of the machine body; a feeding device is arranged at the back end of the machine body; and the machine body is provided with a worktable capable of placing boards.