We investigated the effects of Sarcodon aspratus, Agaricus bisporus, and Lentinula edodes aqueous extracts on the tenderization of bovine longissimus dorsi muscle. Meat quality and muscle protein degradation were examined as well. Beef chunks were marinated in distilled water (control), 5% S. aspratus (SA), 5% A. bisporus (AB), or 5% L. edodes (LE) extracts. SA was shown to have a higher enzymatic activity (p < 0.001) and waterholding capacity than LE (p < 0.01). SA and AB extracts exhibited lower shear force values compared with the control (p < 0.05). SA, AB, and LE showed superior muscle proteolytic effects compared with the control. SA demonstrated the ability to degrade myosin heavy chains and actin, which was not observed after AB and LE extract treatments. This suggests that SA extract may affect tenderization. Taken together, our results show that aqueous extract of S. aspratus affects the tenderness of the bovine longissimus dorsi muscle.