A test device for inspecting electric characteristics of an object to be tested, the test device comprising: a conductive block which comprises a probe hole; at least one signal probe configured to pass through the probe hole without contacting the inner wall of the probe hole, and comprising a first end to be in contact with a testing contact point of the object to be tested, and retractable in a lengthwise direction; a coaxial cable which comprises a core wire having a first end to be in electric contact with a second end of one of the at least one signal probes; and a cable supporter, the test device being characterized in that the cable supporter comprises: a cable supporting block having a cable accommodating hole in which the coaxial cable is accommodated and a transverse plate portion, wherein the cable supporting block is configured to be coupled to the conductive block so that the position of the probe hole is aligned with the position of the cable accommodating hole; and a cable supporting substrate comprising a through hole through which the cable supporting block passes, wherein the cable supporting substrate includes a first side onto which the conductive block is mounted and a second side opposite to the first side to which a second end of the coaxial cable is attached and wherein the transverse plate portion is in contact with the second side of the cable supporting substrate and supports the cable supporting substrate. a conductive block which comprises a probe hole; at least one signal probe configured to pass through the probe hole without contacting the inner wall of the probe hole, and comprising a first end to be in contact with a testing contact point of the object to be tested, and retractable in a lengthwise direction; a coaxial cable which comprises a core wire having a first end to be in electric contact with a second end of one of the at least one signal probes; and a cable supporter, the test device being characterized in that the cable supporter comprises: a cable supporting block having a cable accommodating hole in which the coaxial cable is accommodated and a transverse plate portion, wherein the cable supporting block is configured to be coupled to the conductive block so that the position of the probe hole is aligned with the position of the cable accommodating hole; and a cable supporting substrate comprising a through hole through which the cable supporting block passes, wherein the cable supporting substrate includes a first side onto which the conductive block is mounted and a second side opposite to the first side to which a second end of the coaxial cable is attached and wherein the transverse plate portion is in contact with the second side of the cable supporting substrate and supports the cable supporting substrate. a cable supporting block having a cable accommodating hole in which the coaxial cable is accommodated and a transverse plate portion, wherein the cable supporting block is configured to be coupled to the conductive block so that the position of the probe hole is aligned with the position of the cable accommodating hole; and a cable supporting substrate comprising a through hole through which the cable supporting block passes, wherein the cable supporting substrate includes a first side onto which the conductive block is mounted and a second side opposite to the first side to which a second end of the coaxial cable is attached and wherein the transverse plate portion is in contact with the second side of the cable supporting substrate and supports the cable supporting substrate.