The paper presents an assessment of the degradation of cyclic freeze/thaw on high-strength concretes, based on changes in the stress intensity factor KIC. The degree of HSC destruction due to cyclic freeze/thaw was determined by the longitudinal modulus of elasticity E, weight loss, and wall strength reduction, determined after 150, 250, 300, and 350 cycles and the total mass of surface scaling after 28 and 70 cycles. The degree of degradation was compared with the modification of stress intensity factor values. Three types of high-strength concretes (compressive strength about 90 MPa) were tested: concrete without fibres, concrete with steel fibres in the amount of 0.5% by volume (39 kg/m3) and concrete with a mixture of steel fibres (19.5 kg/m3) and basalt (6.8 kg/m3). The testing methodology is based on RILEM recommendations [1] and ASTM C666 [2] and PKN – CEN/TS 12390 Slab Test [3].