Tricholoma lobayensc heim fruit body was injected by ion beam to induce mutant strains. After treatment, the fruiting yield and biological efficiency of the strains were investigated. As results, a high quality mutant strain was screened out by determining the contents of conventional nutrients including the total sugar, protein, crude fat, crude fiber, and lovastatin (a hypolipidemic component). The results showed that the mutant strain JF-004 had the highest yield (191.60±1.80) g, biological efficiency (76.64%), protein content (35.26%), and crude fiber (9.26%), a moderate total suger, and a low crude fat content, which fits the low-fat and high-fiber dietary pattern and is beneficial to human health. The mutant strain JF-004 also had the highest lovastatin content (10.180 μg·g^-1) in the sporocarp. The results indicated that JF-004 is a high-quality mutant strain.