The invention particularly discloses an improved biphase blood culture bottle which belongs to the technical field of an in-vitro diagnosis reagent. A solid phase of the culture bottle is prepared by mixing brain heart infusion broth, agar powder, yeast extract, nucleic acid and sodium glutamate at a certain weight ratio, and mixing with deionized water. A liquid phase of the culture bottle is prepared by mixing brain heart infusion broth, yeast extract, sodium polyanetholesulfonate (SPS), coenzyme I, vitamin B6, vitamin B1, vitamin B12, L-glutamine, L-cystine, L-cysteine hydrochloride, adenine sulfate, guanine hydrochloride, ferric nitrate and p-aminobenzoic acid at certain weight ratio, and mixing with deionized water. The culture bottle with reasonable formulation and complete nutrition components ensures rapid propagation of common bacteria in blood; is more favorable for growth of various fastidious bacteria; greatly improves a positive detection rate and shortens detection time; obtains an accurate and timely culture result; and has great significance for clinical diagnosis and treatment.