NOVELTY - Crop straw feed fermentation inoculant, solid additive and its preparation method, are claimed. The fermentation inoculant comprises fungi, Actinomyces and bacterium including (a) Myceliophthora thermophila (ACCC-30571) or (ATCC48102), where the M.thermophila is a cellulose degrading bacteria cultured using culture medium 0014 at 45-60 degrees C, and (b) Myrothecium roridum (ACCC-30481), where the M.roridum is a cellulose degrading bacteria cultured using culture medium 0014 at 25-28 degrees C.    USE - The crop straw feed fermentation inoculant is useful as a solid additive for decomposing and softening straw fibers, agroecological feed additive, and substitute product of antibiotics for reducing infection of chemically harmful substance.    ADVANTAGE - The straw feed fermentation inoculant improves palatability, animal digestion capability and straw utilization efficiency, and is safe as it degrades pesticide residue in straw.    DETAILED DESCRIPTION - Crop straw feed fermentation inoculant, solid additive and its preparation method, are claimed. The fermentation inoculant comprises fungi, Actinomyces and bacterium chosen from (a) Myceliophthora thermophila (ACCC-30571) or (ATCC48102), where the M.thermophila is a cellulose degrading bacteria cultured using culture medium 0014 at 45-60 degrees C, (b) Myrothecium roridum (ACCC-30481), where the M.roridum is a cellulose degrading bacteria cultured using culture medium 0014 at 25-28 degrees C, (c) Trichoderma sp. (ACCC-30791), where the Trichoderma sp. is a cellulose degrading bacteria separated from straw and cultured using culture medium 0014 at 25-28 degrees C, (d) Streptomyces albocyaneus (ACCC-40132), where the S.albocyaneus is a cultured using culture medium 0012 without using sucrose, starch and cellulose at 30 degrees C, (e) Saccharomonospora glauca (ACCC-41055), where the S.glauca is capable of degrading cellulose, and is separated from composted garbage, and cultured using culture medium 0455 at 37 degrees C, (f) Lactobacillus sp. (ACCC-03877), where the Lactobacillus sp. is a separate from soil of haidian district in Beijing area, and cultured using culture medium 0002 at 26 degrees C, (g) L.alimentarius (ACCC-10173), where the L.alimentarius is cultured using culture medium 0006 at 37 degrees C, (h) Bacillus subtilis (ACCC-01698), where the B.subtilis is separated from Zhejiang jiaxing pond, and cultured using culture medium 0002 at 37 degrees C, and (i) B.subtilis (ACCC-11025), where the B.subtilis is cultured using culture medium 0002 at 30 degrees C.