Abstract: There are five peaks in the absorption spectrum of phycobilisome thylakoid membrane of Synechococcus leopoliensis 625, they are located at 420nm, 438 nm, 490 nm, 624 nm and 678 nm. The oxygen evolution rate of phycobilisome-thylakoid membrane is 161-197 micromoles oxygen per hour, per milligram chlorophyll. The electron micrograph show that there are a lot of phycobilisomes on the thylakoid membrane.