This study investigated the life cycle greenhouse gases (GHG) mitigation effect of railway infrastructure through the application of an eco-concrete, using ground granulated blast furnace (GGBF) slag and electric arc furnace (EAF) slag as alternative materials in railway sleeper, and a concrete surface protection agent in railway track. A simplified life cycle assessment method was applied to compare GHG emissions and an instrumental analysis as well as a physical performance test were carried out to identify the protection mechanism between the agent and concrete along with field tests. From this study, it was found that two different approaches might contribute substantially to mitigate emissions from railway infrastructure. The surface protection agent with an anti-deterioration function showed high possibility of increasing lifespan of the concrete structure and the use of alternative materials, such as furnace slag, reduced the concrete consumption by more than 20% (w/w). It was estimated that the potential GHG mitigation effects from the surface protection agent and eco-concrete technology applied to a railway concrete track were at least 27 ton CO₂ eq. per km a year and 11.1 kg of CO₂ eq. per 1 sleeper, respectively.