Objective To isolate algicolous fungi from algae and obtain antitumor strains.Methods Selective isolation of algicolous fungi from algae was done,and antitumor activity corresponds to their lethiferous effect on brine shrimp and cytotoxicity against K562 cell was determined.Results 221 strains of algicolous fungi were isolated from 28 algae samples collected from intertidal zones of the Yellow Sea.Eight strains showed lethiferous activity and eight showed cytotoxicity.Conclusion The results indicated that algicolous fungi would be one of the important resources to search for new antitumor compounds.