A wiring substrate that allows wiring at a fine pitch and has a coefficient of thermal expansion close to the coefficient of thermal expansion of silicone, and a probe card that includes the wiring substrate are provided. To this end, there are provided a wiring substrate that includes a ceramic substrate having a coefficient of thermal expansion of 3×10−6 to 5×10−6/° C. and one or more thin-film wiring sheets stacked on one surface of the ceramic substrate, and a probe head on which a plurality of conductive proves are arranged in accordance with wiring on the thin-film wiring sheet, which holds individual probes while preventing the probes from coming off and allowing both ends of each probe to be exposed, and which is stacked on the wiring substrate while one end of each probe is brought into contact with the thin-film wiring sheet.