Abstract. Government-funded R&D initiatives have been playing crucial roles for developing photonic networks. The R&D project is typically carried out for a relatively long period of five-years, and the goal is set so high that no single private sector can afford the risk. In this paper, challenging governmentfunded R&D initiatives of photonic networks in Japan is introduced. They have been launched in 2006, which aims to establish the photonic platform to provide abundant bandwidth on demand, at any time and from anywhere, to promote bandwidth-rich networked applications. In addition, other governmentfunded R&D activities relevant to the photonic networks in Japan is also presented, including photonic devices and subsystems and large-scale optical interconnect for ultra-high performance computing.