Abstract: Study on chromophoric dissolved organic matter (CDOM) of four land-based outfalls, named Dailiao (DL), Xinglin (XL), Tong’an (TA) and Xiang’an (XA) in Xiamen Bay, was carried out in Aug 2009, May 2010 and Aug 2010. The CDOM absorption coefficient at 355 nm, ag(355), ranged from 2.84 -15.91 m-1 and the average was 7.85 m-1 at the outfalls. The ag(355) of outfalls adjacent sea water varied from 0.47-12.50 m-1 and the average was 1.54 m-1. Positive linear correlation was found between ag(355) and COD, BOD5 concentration and the correlation of COD (R2=0.745) is better than BOD5 (R2=0.629). We also applied the PARAFAC method to the study of three dimensional fluorescence excitation-emission matrix. Three components were distinguished and W2 component was detected that rarely exited in natural water body and was similar to X component, moreover, it could be considered as a characteristic fluorescence component of outfalls and adjacent sea water.