This invention relates to stepless speed change bench drill, comprising a pedestal, a vertical post mounted on the pedestal, a worktable and a cabinet mounted on the vertical post, a driving shaft and a main shaft mounted on the upper portion of the cabinet, a motor for transmitting power to the driving shaft, a motor movable wheel and a motor stationary wheel mounted on the driving shaft, and a main shaft movable wheel and a main shaft stationary wheel mounted on the main shaft, a speed regulation shaft provided with a threaded section and mounted between the driving shaft and the main shaft, the threaded section is engaged with a threaded hole formed on a bearing block, the bearing block is simultaneously mounted on the main shaft, the speed regulation shaft is rotated by a speed regulation hand wheel.