Abstract: To compare healing effect on porcine respiratory diseases,pigs were treated with rifampicin,amikacin and a combination of penicillin and streptomycin,respectively.The period of treatment was 4 d.The pigs of group I treated with rifampicin had a cure rate of 87.1% and effective rate of 100%.The pigs of group II treated with amikacin had a cure rate of 34.4% and effective rate of 87.5%.The pigs of group III treated with the combination of penicillin and streptomycin had a cure rate of 28.1% and effective rate of 84.4%.As checked by χ^2 test,the healing effect was significantly different between the group I and the group II or between the group I and the group III （P〈0.01） but not significantly different between the group II and the group III （P 〉0.05）.The healing effect of the group I was 50% higher than that of the group II and 60% higher than that of the group III.