A probe card that electrically connects a semiconductor wafer as a test object and a circuit structure for generating a signal for a test, the probe card comprising: a plurality of probes that are made of a conductive material and come into contact with the semiconductor wafer to receive or output an electric signal; a probe head that houses and holds the probes; a substrate that is flat and has a wiring pattern corresponding to the circuit structure; a reinforcing member that is mounted on the substrate and reinforces the substrate; an interposer that is stacked on the substrate for connection of wires of the substrate; a space transformer that is interposed and stacked between the interposer and the probe head and transforms intervals among the wires to be connected through the interposer, the wires coming out on a surface of the space transformer facing the probe head; a plurality of first post members that have a height greater than a thickness of the substrate, and are embedded in the substrate in a portion of the substrate, on which the interposer is stacked, said plurality of first posts members penetrating through the substrate; and a first fastening member (201, 202) for fastening the interposer to the substrate, wherein the first fastening member (201, 202) includes a plurality of first screw members (201, 202) inserted through at least one of the reinforcing member and the interposer, characterized in that: end faces of each of the plurality of first post members in a thickness direction of the first post member abut the reinforcing member and the interposer such that the height of said plurality of first post members defines the width in the thickness direction of the portion of said substrate. a plurality of probes that are made of a conductive material and come into contact with the semiconductor wafer to receive or output an electric signal; a probe head that houses and holds the probes; a substrate that is flat and has a wiring pattern corresponding to the circuit structure; a reinforcing member that is mounted on the substrate and reinforces the substrate; an interposer that is stacked on the substrate for connection of wires of the substrate; a space transformer that is interposed and stacked between the interposer and the probe head and transforms intervals among the wires to be connected through the interposer, the wires coming out on a surface of the space transformer facing the probe head; a plurality of first post members that have a height greater than a thickness of the substrate, and are embedded in the substrate in a portion of the substrate, on which the interposer is stacked, said plurality of first posts members penetrating through the substrate; and a first fastening member (201, 202) for fastening the interposer to the substrate, wherein the first fastening member (201, 202) includes a plurality of first screw members (201, 202) inserted through at least one of the reinforcing member and the interposer, characterized in that: end faces of each of the plurality of first post members in a thickness direction of the first post member abut the reinforcing member and the interposer such that the height of said plurality of first post members defines the width in the thickness direction of the portion of said substrate.