Low molecular weight (LMW) fucoidan, obtained by free radical depolymerization of high molecular polysaccharide extract of brown algae Hizikia fusiformis, was complexed with HPLC purified bee venom melittin. Water soluble form of the LMW fucoidan:melittin complex shows increased anti-inflammatory activity, inhibiting the production of nitric oxide in murine macrophage cell line Raw 264.7. The LMW fucoidan: melitin complex obtained in this study showed good biological activities, resulting in 2-fold reduction of the melittin toxicity. The fucoidan:melittin macromolecular complex obtained should be useful in future therapeutic applications.