In the present invention, the upper part of the treatment device, the left part of the treatment device, and the right part of the treatment device, provided with a phototherapy module part or a thermal treatment module part on one side thereof, are made to be detachable from each other, and a control part controlling the phototherapy module part and the thermal treatment module part is a treatment device. It is built in the upper part, and is used as a tunnel-type skin treatment device by simply attaching the upper part of the treatment device, the left part of the treatment device, and the right part of the treatment device. The present invention is a skin treatment device comprising a phototherapy module part or a thermal treatment module part and a combination of an upper part of the treatment device, a left part of the treatment device, and a right part of the treatment device, comprising a first upper connection groove in the center of the left and right sides of the treatment device, and the treatment device A first side connection convex portion protruding in the center of the upper left portion of the treatment device is provided, and the first side connection convex portion in the left portion of the treatment device is detachably attached to the first upper surface connection groove on the left side of the treatment device, and protrudes in the central portion of the upper portion of the right side of the treatment device. A first side connection convex portion is provided, and the first side connection convex portion on the right side of the treatment device is detachably attached to the first upper connection groove on the right side of the treatment device, and when the upper part of the treatment device and the left part of the treatment device and the right part of the treatment device are combined, it forms a tunnel shape. Characterize. On the sidewall of the first upper connection groove on the upper part of the treatment device, a connector for co
