The invention discloses a disc type tool magazine for a horizontal machining center. The disc type tool magazine comprises a disc arranged on a fixing support I, a rotation shaft is arranged at the center of the disc which rotates around the center of the disc through the rotation shaft, a plurality of tool clamps are installed at the edge of the disc, and axes of tool holding portions of the tool clamps are parallel to the surface of the disc. Tools are installed on the tool clamps through the tool holding portions, axes of the tools are parallel to the surface of the disc, and tool noses of the tools point to the circle center of the disc. The fixing support I is installed on one side of the horizontal machining center, and the axis of the disc is parallel to the X axis of the horizontal machining center. By means of the disc type tool magazine, the width of the tool magazine is not limited by the length of the tools and can be further compressed, the structure is simple and compact, and wide application is facilitated.