The scale of reinjection pipeline in high-salinity oilfield in Northwest China was serious, many kinds of bactria bred, and there was serious corrosion under scale.In order to reduce bacterial corrosion to the oilfield reinjection water pipe , a kind of high efficient antimicrobial and corrosion inhibitor was developed.Through the combination of antimicrobial di-decyl dimethyl ammonium chloride and several kinds of D-amino acid, it was realized with sterilization rate all higher than 96% for saprophytic bacteria which attached to scale, iron bacteria and sulfate reducing bacteria which attached to scale.Besides, the effect of time and temperature on the sterilization rate of the combined antimicrobial was investigated.Results showed that the sterilizing rate of this kind of combined antimicrobial increased as the sterilizing time lengthened and reached nearly 100% after 12 h.In saline solution with temperatures ranging from 40 ℃ to 70 ℃, the sterilizing rates were higher than 97.5%, showing an excellent stability toward temperature.Meanwhile, the addition of several kinds of D-amino acid conferred the combined antimicrobial and corrosion inhibitor with certain corrosion inhibition ability.Thus, this kind of antimicrobial corrosion inhibitor could be an ideal alternative to relieve the corrosion situation of high-salinity oilfield reinjection water tubes.