Although the production and application of iron and steel were delayed by about 100 years in Japan compared with those in Europe and the US, Japan is one of the most advanced countries in both steel production and application at present. This was made possible because of extensive R&D activities on technologies for production of steel, steel materials, and various structural steel systems. Since Japan is one of the most seismically active areas in the world, steel structures have played an important role in securing safety against frequent and large earthquakes that have left tremendous damage and human losses in the past. Japan domestically consumes about 50 million tons of steel every year, and approximately 45% of the steel is used for the construction market. Although Japan has been reaching an economically mature stage, the Japanese industry of steel and steel structures may expect further growth in steel consumption for buildings and infrastructure because of strong current demands for renovations, renewals, and even urban redevelopment. In this paper, starting with the overview of steel buildings in Japan, development of some of the advanced steel materials including high-strength steels and seismic-resistant steels is outlined in detail with their backgrounds. Some of the advancements are motivated by frequent large earthquakes; therefore, the relations with seismic design are stressed.