A connection structure for a dental abutment is such that an embedded part of a dental base part to fit to an oral cavity side of an implant fixture embedded in a jawbone is inserted into and connected to an insertion hole of a dental cutting block part, wherein the dental cutting block part includes a first flat surface and a protrusion on an inner peripheral surface of the insertion hole, and wherein the dental base part includes, on an outer peripheral surface of the embedded part, a second flat surface that corresponds to the first flat surface.
