As a result of analyses of the effect of high voltage electrical stimulation (voltage of 330 V, frequency of 17 Hz, duration of 120 s) carried out ca. 40 min after slaughter on tenderness of bullocks (n=8) meat, lower values of the maximum shear force were obtained for the stimulated muscles (except for semimembranosus muscle stored for 144 h) as compared to its values noted for control muscles over the entire storage period. In addition, values of the maximum shear forces of stimulated, fresh m. longissimus dorsi and m. semimembranosus were alike and reached ca. 44 N. Results of analyses into the effect of storage time (144 h) on meat tenderness demonstrated that differences between the values of the maximum shear forces of the stimulated and control m. semimembranosus were decreasing along with time, whereas differences between the values of shear forces of m. longissimus dorsi (stimulated and control) were remaining at a constant level (ca. 30 N). The results obtained demonstrated that high voltage electrical stimulation, by means of an own-construction device, improves tenderness of the muscles examined.