Steel-concrete composite beam bridge structure used more and more widely with the application and development of bridge technology in our country,in order to improve its fatigue life during steel-concrete composite beam bridge construction,increase the measures to prevent corrosion becomes more and more important in the steel structure bridges of annual increased.This article studied the surface coating system and coating technology for dry cold environment in northwest.Summarized the measures to prevent corrosion for suitable northwest environment.With the purpose to useful experiences for steel bridge protection of northwest environmental in our country with this study.