The problem between a crack and a hole has a very important meaning from the viewpoint of fracture mechanics. In practice, inclusions inside materials often become the cause of stress intensity or destruction of the materials, so that the use of a mechanical modeling, regarding a hole as a defective material or air inclusions, will enlarge the scope of application.<BR>From this viewpoint, in this paper, the stress intensity factor K<SUB>I</SUB> is investigated by a caustic method experimentally, when a block with a tiny hole at the tip of the crack is transiently heated-loaded. The results are as follows: the non-dimensional expression of the relation between K<SUB>Imax</SUB> and the crack length and the distance to the center of the tiny hole from the crack tip makes a curve.