Anacardium occidentale gum are composed by complex heteropolysaccharides. This material is soluble in water forming a low viscosity solution that can be precipitated by organic polar solvents. Synthetic and natural polysaccharide are used for enzyme immobilization due their versatility of chemical reactions. In this work a cashew gum polysaccharide (CGP) was extracted, partially characterized and used for horseradish peroxidase (HRP) immobilization. Grounded samples of CGP were immersed in distilled water 20% w/v at 25ºC for 24h. The CGP was precipitated with ethanol (1:3v/v) for 24h, filtrated,  dried at 25ºC, grounded, and stored. Solution of CGP prepared at 25 and 65ºC were analyzed by chromatography on a Sephadex G-75 column (22x1.5cm) and fractions analyzed at 280nm. Protein content was analyzed by Bradford (1976) assay in samples dissolved in water at 25, 35, 45, 55 and 65ºC. The immobilization of HRP was performed adding increasing amounts (from 250 to 1000µL) of HRP solution (24U mL^-1) to 15mg periodate activated CGP. The reaction proceeded for 30min at 4ºC. After that, the CGP-HRP was precipitated by absolute ethanol, the supernatant separated by centrifugation, and immobilized HRP activity tested with 1.4mL of a solution containing 0.1mol L^-1 phosphate buffer pH 6.0, 0.5mL of 0.05mol L^-1 hydrogen peroxide and 1.0mL of 0.07 mol L^-1 pyrogallol (420nm). The chromatograms showed that CGP soluble at 25ºC presented three main peaks of high molecular mass, four of intermediary and two of low molecular mass. Otherwise, the CGP soluble at 65ºC showed peaks of extremely varied molecular mass, and fragments of very low molecular mass. The fraction of soluble protein increased as function of temperature, reaching values of 13,54µg/mL at 65ºC. It seems that solubilization of the protein was a consequence of disruption of physical entanglements that were sustained polysaccharide chain, as showed the chromatograms. CGP was very efficient for HRP immobilization, with 100% yield when 1000L of HRP solution reacted with 15mg CGP. CGP is a very promising material for HRP immobilization, due its high capacity of enzyme retention, water solubility and easy recovery by simple precipitation with ethanol.