This study was conducted to investigate the proteolytic properties of Sarcodon aspratus on meat proteins. The analytical condition for the measurement of enzyme activity was determined and the effect of Sarcodon aspratus on beef protein and its fractions were determined by SDS-PAGE and spectrophotometric method, respectively. Optimum temperature and pH of Sarcodon aspratus was $73-78^{\circ}C$,pH 8, respectively. However, the enzyme tended to be denatured at $50^{\circ}C$ for 10min incubation. Proteolytic activity of Sarcodon aspratus was higher than those of kiwi and pear by 66 and 990 times by dry weight, respectively. It was appeared that proteolytic activity of Sarcodon aspratus toward beef protein by SDS-PAGE was prominent when compared to those of kiwi and bromelain. Furthermore, Sarcodon aspratus showed highest proteolytic activity toward all the beef protein fractions, which was followed by collagenase and bovine protease. Transmission electron microscopy showed the muscle fiber started to be degraded when treated with Sarcodon aspratus(1,000 unit) for 10min at $25^{\circ}C$. No distinct sarcomere, A-band, and z-line was observed when treated with Sarcodon aspratus for 60min at same condition.