The following paper contains importance of LCA in the iron and steel industry. The metallurgy sector is highly energy intensive and the production of crude steel is associated with significant CO2 emissions. ULCOS (Ultra Low CO2 Steelmaking) is the world’s initiative to reduce carbon dioxide emissions by 50 % by 2 050 compared with today’s best routes from steel production by developing new breakthrough technologies. A new environmental Life Cycle Assessment (LCA) method has been undertaken in ULCOS as the most holistic approach of assessing environmental impact and selecting new technologies. Usage of LCA enables to compare alternative metallurgical technologies.