An FTTH optical access network architecture based on ''three-network integration'' belongs to the application field of multi-network fusion technology. The FTTH optical access network architecture comprises the following components: an accessed telecommunication public network, an accessed Internet, wireless transmission, a broadcast television access network, the existing local area network fireproof wall of the enterprise, the existing local area network core switch of the enterprise, a media gateway, a three-network integrated first-core switch session boundary controller, the fireproof wall, the switch, a NGN soft switching system, a narrowband charger, a network management system, a first database server, an intelligent service gateway, a gigabit Ethernet passive optical network GPON,an optical fiber line terminal device EPON, an optical amplifying unit, an ONU, a digital monitoring system, a wideband charger, a security service gateway, a server, an optical splitter, an AP, an optical network terminal ONT, an optical network terminal with a wireless home gateway, an optical network terminal M3-2401, an integrated access device and an integrated service aceess plateform. TheFTTH optical access network architecture of the invention has the advantages of multi-network fusion, high bandwidth, high stability, low input and high return.