Abstract: The bag cultivation of shiitake with bagasse substratum sterilized by germicide was investigated.The result showed that,using MD908 germicide in the bagasse substratum to substitute the procedure of autoclav-ing,the shiitake strains L11 and L12 which were selected from 12 shiitake strains grew and developed well.The suitable hyphal age is around 40 days.The bagasse substratum preperation,inoculation and incubation were undertaken under indoor condition at 25-28℃.The contaminated rates of Lll and L12 were 2.45% and 2.40%,the bio-efficiencies of L11 and L12 were 78.97% and 69.15% respectively.Only 0.0015% of benzoic acid was found in dry mushroom in the treatment using MD908 germicide to substitute the auto-claving,which is quite lower than the residual limitation in food products.