Candida rugosa lipase was immobilized on poly(vinyl alcohol) microspheres using a cross-linking method. The effects of this immobilization on the thermal and pH stabilities of lipase were investigated. Immobilized lipase showed better pH stability and resistance to acidic environments than free lipase, and higher temperature stability up to 45°C. The effect of reuse on the activity of immobilized lipase was also investigated. It was found to retain over 50 % of its original activity after 10 cycles of reuse.