the access bandwidth demand increase day by day. Gigabit Passive Optical Network(GPON) with fiber to the home(FTTH) and fi ber to the building(FTTB) mode is widely utilized in wired access network. GPON with FTTH mode can provide 100Mbit/s bandwidth. FTTB users which linked to one PON port with more than 188 product of ONU port and splitter port cannot meet 50Mbit/s bandwidth. Three evolutional strategies of FTTB access network are analyzed in this paper. Each of the three strategies has its advantages and disadvantages. The implementation of those upgrade strategies should be based on the coverage situation of information point and appropriate ways.