Abstract: In order to investigate the mechanism of the beef tenderness, 24 hybrid cattle (Chinese Yellow cattle crossed with Simental) of 24 months and 500kg were chosen to be divided into four groups and treated with four method such as conventional chilling, electrical stimulation, delay chilling, combination of electrical stimulation and delay chilling. Effects of electrical stimulation and delay chilling on the degradation of skeleton protein Troponin-T from myofibrillar were studied with SDS-PAGE and Western blotting at the aging time of 1, 3, 7,10 days. The results show that compared with conventional chilling treatment, the effects of electrical stimulation on the degradation of Troponin-T have obvious difference in 1, 3, 7 aging days, but no obvious difference in 10 aging days, while the one of delay chilling had obvious difference in 1, 3 aging days, but no obvious difference in 7, 10 aging days. The effect of the combination of electrical stimulation and delay chilling on the degradation of Troponin-T is more obvious than that of electrical stimulation or delay chilling. It can be concluded that electrical stimulation and delay chilling increase the degradation of Troponin-T not only in velocity but also in quantity, shorten the aging time and had cooperative effect.