The material properties of a carbon-carbon brake disk were measured by static tests. The static strength was tested for each slot in a carbon-carbon rotor disk which is the stress critical part of a carbon-carbon brake system during operation. A loading fixture was designed for the static strength test of a single carbon-carbon rotor disk. To simulate the real dynamic system in a static condition, the friction surface of the rotor disk was clamped and static load was applied to a slot in the circumferential direction of the rotor disk. The described failure mechanism of the brake disk can be described as a sequence of the multiple matrix cracks at the contact surface of the rotor slot, subsequent delaminations from the cracked contact surface, and the final fracture at the notch of the slot. To investigate the mechanical behavior upon the different slot shapes, FE analysis was used. The rotor with slots of the acute sliding angle had the smallest Tsai-Wu failure index.