A circular saw machine contains a first clamping device, a second clamping device, a holding plate, a feeding means, and a sawing device. The first clamping device includes a first clamp mount, a movable clamp block, and a first upper clamp block, the first clamp mount has a first fixing arm, a first holder, a placing portion and a first fixed clamp block. The second clamping device includes a second clamp mount, a second movable clamp block, and a second upper clamp block, the first clamp mount has a second clamp arm, a second holder, and a second fixed clamp block. The holding plate is secured on a top end of the second clamp arm. The feeding means is disposed on the first clamping device. The sawing device includes a saw disc.