The performed experiment on semi-intensive fattening of the crossbred bulls /25, 50 and 75% HF,Red/ showed that the best fattening ability parameters had the crossbred F₁, those fattened up to the final body weight 550 and 600 kg. The crossbred bulls with 25% HF blood had the worst results, while those with 75ft HF had the intermediate results. The crossbred bulls were worse in dressing percentage by 2,66 to 4,05ft, in comparison with the pure-bred animals /difference statistically significant or highly significant/. Better results for fattening ability traits and for some indices of slaughter value had those crossbred bulls fattened up to 600 kg body weight.