In order to improve the clinical diagnosis efficiency of bovine respiratory disease complex （BRD） with multiple pathogen mixed infection，this study established a real-time quantitative PCR （qPCR） for multiple and rapid detection of seven common pathogens of BRD including Mycoplasma bovis （M.b），Pasteurellae multocida （P.m），Mannheimia haemolytica （M.h），bovine infectious rhinotracheitis virus （IBRV），bovine syncytial virus （BRSV），bovine parainfluenza virus type 3 genotype a （BPIV-3a） and c （BPIV-3c），the specific primers and TaqMan probes were designed and synthesized for the oppD/F gene of M.b，gcp gene of M.h，ompH gene of P.m，gB gene of IBRV，N genes of BRSV，BPIV-3a and BPIV-3c，respectively. After optimizing the reaction conditions，a multiple qPCR was established for simultaneous detection of the above seven pathogens in three tubes. This method specifically amplified these seven pathogens，rather than other major pathogens commonly found in cattle，indicating a high specificity. For M.b，P.m，M.h，IBRV，BRSV，BPIV-3a and BPIV-3c，the analytical sensitivity as limit of detection （LOD） was 10² copies /μL，10² copies /μL，10¹ copies /μL，10² copies /μL，10² copies /μL，10² copies /μL，10² copies /μL and 10¹ copies /μL，respectively，suggesting a high sensitivity. In addition，the coefficient of variation of the method was less than 2.5% within group and 5.5% between groups，indicating a good repeatability. Furthermore，115 clinical nasal swabs were parallelly detected by this method and conventional PCR，and the positivity was 27.83% for M.b，36.65% for P.m，25.22% for M.h，11.30% for IBRV，0.95% for BRSV，8.57% for BPIV-3C，with the proportion of coinfection was 26.1%. A total of 11 mixed infection patterns were detected，among them，the coinfection rate of M.b with other pathogens was the highest，accouning for 72.7% （8/11）. Within the 30 coinfection cases，the detection rate of M.b/P.m coinfection was the highest （60%，18/30）； the top three pathogens present in the coinfection were M.b，P.m，and M.h with frequency of 73.3% （22/30），73.3% （22/30） and 43.3% （13/30），respectively； followed by IBRV （26.7%，8/30） and BPIV-3c （13.3%，4/30）. Overall，this method has high sensitivity and specificity，and potential application in the clinical detection of single pathogen and multiple pathogens causing BRD.