The separation of soluble or insoluble materials from solutions is difficult when their concentrations are relatively small, and in such occasions, most of the available separation techniques become inefficient. The problems associated with separation of solutes from dilute solutions become more serious if components that are involved are sensitive to changes in the operating conditions like temperature, such as enzymes. Groups of methods, which appear to be useful for separating almost any material, particularly when its bulk concentration is low, are called foam separation techniques and/or adsorptive bubble separation techniques. The separation and recovery of proteins is usually carried out by chromatography, ultrafiltration and precipitation techniques. In recent years, the relatively high cost of these methods has led to greater interest in less costly purification alternatives. Foam fractionation is simple, relatively inexpensive and in commercial practice, it has significant potential for reducing the high cost of protein recovery. Alpha amylase, the material used in this study is one of the most of the enzymes used in the starch industry and related industries. Today, alpha amylase is used for starch hydrolysis in industries such as food industry, detergents, textiles and paper industries. In this study, extraction, separation, and enrichment of alpha amylase solutions were studied by continuous foam fractionation. Effects of various operating parameters such as gas flow rate, and solution parameters such as initial feed concentration of enzyme, surfactant concentration, surface tension, type of surfactant, mixture of surfactants, ionic strength, type of salt and initial pH of solution on recovery and enrichment of the enzyme were investigated. In this study, a homemade polycarbonate-foam-fractionation column was used. The height of the column was 60 cm, and the inner and outer diameters were 4.4 cm and 5 cm, respectively. The gas distributor had the pore size of 5 to 10 micrometers. The power of the feed pump was 7.55 W, and a nitrogen gas cylinder equipped with a pressure regulator and a gas flow meter provided the required gas phase. An electrical current regulator was used to change the pump flow rate. The results of this study show that the most favorable nitrogen flow rate was one lit/min. The optimum initial concentration of the feed solution was 10 mg/lit, and a pH of 7.2 was the most desirable pH value. The initial concentration of surfactant was fixed at 200 mg/lit, and this concentration provided the optimum enrichment. Effect of surface tension in various surfactant concentrations on enrichment ratio was studied, and the results showed that the enrichment ratio is enhanced as the surface tension is increased. The ionic strength of KCl was studied and results showed that maximum enrichment is achieved at a concentration of 0.02 mol/lit. Effect of other salts, such as KBr and Na 2 SO 4 on process performance were also investigated. The highest enrichment was recorded for Na 2 SO 4 . Among various surfactants used, nonionic type surfactant was the most desirable. Binary mixtures of surfactants as a new parameter were tested, and the best result was obtained with mixed cationic /anionic surfactant. Keyword : Separation, alpha amylase, surfactant, recovery and enrichment