Provided is a blood culture treatment technology, including a novel treatment technology of performing pretreatment of a positive blood culture to effectively remove foreign substances such as cells, etc., thereby omitting a subculturing process on a solid medium and realizing rapid selection of antimicrobial agents for patients. The pretreatment method of a positive blood culture sample for bacterial identification and antimicrobial susceptibility testing includes preparing a first liquid culture by centrifuging a portion of a liquid medium including the positive blood culture sample, washing a precipitate thus centrifuged with a solution including sodium chloride, and then suspending the precipitate in the solution including sodium chloride, and preparing a second liquid culture by passing the first liquid culture thus prepared through a pretreatment filter including a mesh structure.