The adsorption efficiency of five home-made resins and Amberlite XAD-2 resin forhumic substances in seawater are compared.1.GDX-102 resin,a home-made adsorbent,could effectively adsorb the hydrophobicorganic matters,rather than the hydrophilic ones such as amino acids and sugar.Underthe same conditions,the amount of humic substances and ethenol-soluble matter adsorbedon GDX-102 resin were respectively 2.24 and 1.23 times more than that on Amberlite XAD-2 resin,and the water flow rate through GDX-102 resin column was 1.5 times faster thanthat through XAD-2 resin.Thus,GDX-102 resin is proved to be an effective adsorptionresin for isolating humic substances from seawater.2 The fulvic acids isolated with GDX-102 and Amberlite XAD-2 resins were chemi-cally characterized by determining their elementary composition,ultraviolet absorption spectra,E_4/E_6 ratio,infrared absorption spectra and gel electrophoresis pattern.The comparisonof FA of seawater with that of soil showed a close similarity between them.3.After elution of humic substances from GDX-102 resin with alkali,an ethanol-solublematter and an ether-soluble matter were isolated by elution with ethanol and ether suc-cessively.The former seemed to be organic compounds differing from FA both in elementary composition and in infrared absorption spectra and containing more hydrophobic portions,and the latter was identified by liquid chromatograph to be the polynuclear aromatic hydro-carbons(PAH).The GDX-102 resin,therefore,might as well be an effective adsorptionresin for isolating PAH from seawater. The adsorption efficiency of five home-made resins and Amberlite XAD-2 resin for humic substances in seawater are compared.1. GDX-102 resin, a home-made adsorbent, could effectively adsorb the hydrophobicorganic matters, rather than the hydrophilic ones such as amino acids and sugar. Underthe same conditions, the amount of humic substances and ethenol-soluble matter adsorbed on GDX-102 resin were respectively 2.24 and 1.23 times more than that on Amberlite XAD-2 resin, and the water flow rate through GDX-102 resin column was 1.5 times faster thanthat XAD-2 resin.Thus, GDX-102 resin was proved to be an effective adsorption for in isolating humic substances from seawater.2 The fulvic acids isolated with GDX-102 and Amberlite XAD-2 resins were chemi- cally characterized by determining their elementary composition, ultraviolet absorption spectra, E_4 / E_6 ratio, infrared absorption spectra and gel electrophoresis pattern.The comparison of FA of seawater with that of soil showed a close similarity between them.3.After elution of humic substances from GDX-102 resin with alkali, an ethanol-solublematter and an ether-soluble matter were isolated by elution with ethanol and ether suc-cessively. The former seemed to be organic compounds differing from FA both in elementary composition and in infrared absorption spectra and containing more hydrophobic portions, and the latter was identified by liquid chromatograph to be the polynuclear aromatic hydro-carbons (PAH). The GDX-102 resin, therefore, might well be an effective adsorptionresin for isolating PAH from seawater.