The invention discloses a multiplex SYBR Green I real-time fluorescence PCR (polymerase chain reaction) detection primer and method for porcine rabies virus, porcine parvovirus and porcine circovirus type 2. The primer is obtained through synthesis according to design. The multiplex SYBR Green I real-time fluorescence PCR detection method for detecting porcine rabies virus, porcine parvovirus and porcine circovirus type 2 by utilizing the primer comprises the following steps: extracting the DNA of a sample, and then, detecting the sample by utilizing a SYBR Green I real-time fluorescence PCR reaction system and a SYBR Green I real-time fluorescence PCR amplification program. The invention has the beneficial effects that three types of viruses, namely the porcine rabies virus, the porcine parvovirus and the porcine circovirus type 2, can be simultaneously and effectively diagnosed and detected; non-specific swine fever virus, porcine reproductive and respiratory syndrome virus and swine influenza virus can not be detected; and the invention is beneficial to identification and diagnosis of the breeding disorder virus of a pregnant swine, and has better sensitivity, repeatability and stability.