<p indent="0mm">This paper studies the calculation method of carbon emissions throughout the life cycle of steel materials covering all stages of manufacturing, transportation, installation, service, and recycling. Taking steel pipelines as an example, this paper explores the impact of corrosion protection on the life cycle carbon emissions and annual average carbon emissions of steel materials. A carbon emission calculation method for all links in the life cycle of engineering steel materials in corrosive environments has been established. In addition to “carbon emissions per unit GDP (carbon emission intensity),” another intensity index is proposed as “life cycle average annual carbon emissions (carbon emissions per unit time).” This intensity index can constrain the life cycle carbon footprint in the time dimension. It is the first to quantify the important role of corrosion protection in controlling carbon emissions from steel materials at home and abroad. Through. Using appropriate anticorrosion technology, steel pipelines can reduce emissions by more than 60% in typical chemical production environments, more than 83% in oil and gas field environments, more than 50% in long-distance pipelines, and more than 28% in urban gas pipeline networks. This study is important in developing low-carbon corrosion control methods and improving corrosion protection, which controls the life cycle carbon emissions and annual average carbon emissions of steel materials, thereby providing a new perspective for the corrosion protection design and engineering implementation of steel structures. Consequently, it provides a new methodology for reducing carbon emissions of steel materials.