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The compact tension (CT) specimens of beryllium were employed to study the fracture behavior and mechanical properties. The local stress distribution near a notch in CT beryllium was measured by combination of an X-ray stress analysis and a custom-designed load device, and the fracture morphology was observed by SEM. The results show that the local stress near notch tip is much higher than that in other areas, and a cracking occurs firstly in this area. The loading-cracking displacement curve of the CT Be was obtained, and the fracture toughness value was calculated from the curve. The CT specimen fracture surfaces mainly exhibit a cleave morphology with three typical areas. Some open micro-cracks along the basal slip plane were formed in the crack tip, and its growth was controlled by primary stress after reaching a critical length. The tensile strength was evaluated by the fracture toughness theory when a crack existed in the Be material.