Microbiologically influenced corrosion (MIC) is a common phenomenon in oil and gas industries. Sulfate-reducing bacteria (SRB) often leads to MIC and oilfield acidification. Glutaraldehyde is a highly effective biocide, which is used to kill SRB. In this paper, the effect of glutaraldehyde as a biocide against the MIC of X80 steel has been studied by weight-loss tests, electrochemical measurements, and surface analysis techniques. The results show that glutaraldehyde can effectively alleviate the MIC problem caused by SRB. After adding 100 parts per million (ppm) of glutaraldehyde, the number of SRB cells and the corrosion rate of samples decrease significantly. The damage of pitting corrosion caused by SRB on the surface of X80 steel is controlled by glutaraldehyde. Electrochemical measurements corroborate the weight-loss measured data and scanning electron microscopy (SEM) images. [ABSTRACT FROM AUTHOR]