Punching process in thin plates has been applied in large scale in the industry, but when thick plates are considered, generally other methods are used. In these cases, the use of punching reduces the dimensional quality owing to the combination of elevate load and large clearance necessary between punch and die. Considering this facts and the lack of studies about this matter, a punching probe for thick plates at high temperatures was projected, manufactured and assembled in order to evaluate the effects that high temperatures could cause on the quality of the holes. Plates of SAE 5140 at 1100°C, 20 mm thick and 100 mm large, were pierced with a 20,3 mm diameter punch at 5 mm/s. It was used 1% clearance. After the experimental procedure, the dimensional and the main resulting characteristics of the holes were analyzed. The use of a sheet holder strongly reduced rollover which also caused warp reduction. This region represents only 7,5% of the plate thickness. The maximum variation throughout the internal diameter of the holes does not exceed 0,09 mm of the nominal diameter and the maximum circularity found was about 0,1 mm. The fracture zone, which at room temperatures generally is 70% of the thickness, was practically vanish in this experimental procedure. The lower clearance compared to thin sheets, has enabled practically the elimination of the burr. Also, an analysis of the material flow direction near the hole and also the hardness profile of normalized and quenched plates are presented. Generally, the high temperature used in this experimental procedure causes distortions in the material after cooling, however the dimensional precision reached with this process overcame the expectations regarding quality and applicability potential.