In order to establish a multiple PCR method for rapid detection of CDV,CPV,CAV-2 and CPIV,according to the gene sequences in GenBank,four pairs of specific primers were designed for amplifying the four specific fragments of CDV H,CPV VP2,CAV-2 E3 and CPIV NP. By optimization of annealing temperature,a multiplex PCR assay of CDV H(410 bp),CPV VP2(253 bp),CAV-2 E3(655 bp)and CPIV NP(868 bp)was established for simultaneous detection of the four viruses. The DNA or cDNA template of CDV,CPV,CAV-2,CPIV,CDV+CPV+CAV-2+ CPIV and CCV were detected by multiplex PCR,and the results showed that the specificity was good. The multiplex PCR method and the single PCR method were compared with the sensitivity. The results of difference was ten times,and the sensitivity of the multiplex PCR was good. Thirty clinical samples of affected dogs from Beijing City were detected by the multiplex PCR,and the positive rate of CDV,CPV,CAV-2 and CPIV were 63.33%(19/30),33.33%(10/30),6.66%(2/30)and 0(0/30),respectively. The results indicated that the established PCR method could be used for clinical diagnosis.