The construction industry is one of the biggest exploiters of both renewable and non-renewable resources in the world. Therefore, it was unavoidable that concerns will be raised with respect to the environmental effect of this industry. As the procedure of building consume many material through its life cycle, the determination and utilization of sustainable building material were assessed due to their important role in the planning and construction of a green building. This study is set up to show an approach for sustainable building material selection and their effects on nature. It likewise talk about the life cycle assessment as a methodological role and system and its limitation for the examination of sustainable building material. This will be conducted through a comparative analysis of the most common material used in construction industry in Egypt; which are concrete and steel. The analysis investigates the amount of energy consumed and greenhouse gases emitted through out the material life cycle. This study shows that using steel in construction can be less damaging to the environment as well as saving energy used in building life cycle.