Eighteen muscles of young bulls and heifers, both from black and white breed, have been examined. The structure (i.e. the traits: fibre surface, perimysium thickness, endomysium thickness, and the contents of intramuscular fat) was evaluated by means of a computer analysis of a MultiScan picture. Rheological properties were examined using a relaxation test; an Instron 1140 device was applied to carry out the test. It was stated that as for the young bull muscles, the following parameters had higher average values if compared with the corresponding muscle parameters of heifers: the sums of elastic moduli, the fibre surface, and the perimysium thickness. ADD, ST, BF and VM were found to be those muscles, which essentially differentiated the visco-elastic properties of young bull and heifer meat. From among rheological and structure indicators examined, the animal sex had the highest influence on the diversification of perimysium thickness, and the sums of elastic moduli. However, there was a low diversification between sexes with regard to the following parameters: the sums of viscous moduli, the endomysium thickness, the muscle fibre surface, and the intramuscular fat concretions.