A tool box includes a base with a pivotable cover and a tool rack is securely connected to the cover so that when the cover is pivoted to open position, the rack is pivoted with the cover. A shaft rotatably extends through the tool rack and includes a plurality of notches which are located corresponding to through holes defined in the rack. Each notch includes two inclined surfaces so as to clamp a side of an end of the tool inserted into the through hole. By this specific arrangement, the tools are well positioned and do not shake.