A method for inspecting hepatitis and AIDS nucleic acid by synchronized amplification and its reagent knit are disclosed. The process is carried out by taking magnetic ball as automatic medium, specific synchronized capturing HBV, CHV and HIV nucleic acid, accelerating biotin primer construction and purification by RNA external label and internal label, real-time synchronized inspecting and T-PCR amplifying based on Tagman probe. The reagent knit consists of dis-inhibitor, cracking liquid, magnetic ball suspension, washing liquor, internal check, RT-PCR reactive liquor, enzyme mixture, fluorescent mixture, positive check and negative check. It's accurate and automatic, has single-tube operation, closed inspection AND synchronized extraction, and it has better sensitivity and specific performance and can be used for large-scale blood screening and large-capacity clinical inspection.