The invention discloses primers, a probe, a kit and a method used for detecting porcine circovirus 3 based on the digital PCR technology. The primers and the probe comprise an upstream primer FP, a downstream primer BP and the probe Probe; and the detection kit comprises 2XddPCR Supermix, ultrapure water without RNA anzyme, a virus total DNA extracting reagent, a negative control and a positive control. According to the detection method, DNA of a to-be-detected sample is extracted, quantitative detection is carried out on the DNA of the to-be-detected sample by adopting the microdrop digital PCR technology, whether the to-be-detected sample contains the porcine circovirus 3 or not is judged through analysis on the obtained copy number after amplification, and the content of the porcine circovirus 3 is also determined. The primers, the probe, the kit and the method have the advantages that the operation is accurate and sensitive, the applicability is wide, the dependency on a standard curve is eliminated, the absolute quantification can be realized, the early discovery, early treatment and early prevention for the porcine circovirus 3 virus disease diagnosis can be realized, and thus the outbreak of diseases can be effectively controlled.