A hardness tester includes an image acquirer (controller) acquiring an image of a surface (surface image) of a sample captured by an image capturer, an identifier (controller) identifying, based on the surface image of the sample, a non-conformity region inside the image that is unsuitable for the hardness test using predetermined conditions, and a test position definer (controller) defining a test position in an area outside the non-conformity region identified by the identifier.