In order to detect porcine pseudorabies virus (PRV) and porcine circovirus type 3 (PCV3) simultaneously, two pairs of specific primers were synthesized based on the conservative region of the gE gene of PRV and Rep gene of PCV3.A dual SYBR GreenⅠfluorescent quantitative PCR method for the detection of PRV and PCV3 was developed based on the optimization of reaction system and amplification conditions. The results showed that: the Tm values of PRV and PCV3 were 87 and 81.5 ℃, respectively, which could specifically detect PRV and PCV3, while no fluorescent signals were detected for the other five porcine pathogens; The lowest detection values of PRV and PCV3 were 37.0 and 33.8 copies·μL^-1 f, respectively. The coefficients of variation in intra-batch and inter-batch assays were all less than 2.0%. The SYBR GreenⅠ-based duplex real-time RT-PCR assay was then used to detect 78 clinical samples of porcine collected from 2017 to 2019 in Henan Province, and the positive rates of PRV and PCV3 were 19.23% (15/78) and 41.03% (32/78), respectively, while the positive rate of co-infection for PCV3 and PRV was 8.97%（7/78）. It showed that the method has high sensitivity, specificity and stability for monitoring PRV, PCV3 and their epidemiological investigation.