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／ lhis paper deals with influence ofre ｝ ative hole − 【 ayout to 由e in 漁 tion and propagation of the crack around the local hole in one − piece brake disc ， Overload braking tests were carried out with two types of brake disc ， which have same shape of hub part( decoration − windows ) ， hole size and number of holes ， but different hole − layout in circumferential direction ． Thermal stress in hard braking was analyzed by FEM in which constraint temperatUre was applied on the elementa1 nodes observed in actUal thermogTaphy test． Local compliance in circumferential direction around the hole was also evaluated at static state ． ［ ［ he FEM results showed that Iocal stress distribution around the hole was affected by the hole − 1ayout ． lt suggested that the hole − layout changed the crack initiation process in the brake disc due to the compressive themmal stress ， which induced tensile stress with plastic deformation as previous studies show Different crack lengths were observed in two specimens having different hole・ layout in the hard braking test． ／ 1／ he crack Iength was l℃ lated with the locaI circumferential compliance ， This paper proposed that hole − layout should be dete ined as the Iocal compliance in circumf ¢rential is high around the hole where elevated temperature is applied by the braking energy ， Key words ：brake disc ， crack initiation ， crack propagation ， fatigue ， and thermal stress