The present invention relates to a device for selecting the position of a guide drill for dental implant operation, which measures an interdental distance for implanting a dental implant into the middle of the interdental distance in dental implant operation and which guides the drilling position of the guide drill to the middle of the interdental distance. The device for selecting the position of a guide drill for dental implant operation comprises: a housing (2)； a slide member (3) which is contained to be inserted/withdrawn in a receiving room (21) of the housing (2) and which has a body being partially withdrawn when measuring the interdental distance of a patient, wherein a measurement part (31) is marked lengthwise on the slide member so as to allow the position of withdrawal to be indicated by an indication part (24) when the body of the slide member (3) is withdrawn； an elastic member (4) which provides elastic force to allow the slide member (3) to be withdrawn； a first contact plate (5) which is protruding from the outside of the housing (2) and which has an outer surface pressing against one tooth (T1) so as to measure the interdental distance of a patient； a second contact plate (6) which is protruding from the slide member (3) and which has an outer surface pressing against the other tooth (T2) in the withdrawal process for the slide member (3)； and a guide member (7) which has a guide part (71) marked lengthwise thereon, wherein information elements of the guide part (71) are corresponding to information elements of the measurement part (31) on the slide member (3) respectively. In addition, the information elements of the guide part (71) are arranged on the guide member (7) so as to allow the position of each of the information elements of the guide part (71) to become the middle point between the first and second contact plates (5, 6), wherein the information elements of the guide part (71) are corresponding to the information elements of the measure
