Semi-Interpenetrating Polymer Networks (semi-IPN) were prepared by cross linking chitosan and L-alanine with glutaraldehyde as cross linker. A viscous solution of chitosan–alanine was prepared in 2 % acetic acid solution, extruded in the form of droplets by a syringe to NaOH – methanol solution and cross linked with glutaraldehyde. The swelling behavior of cross linked beads in different pH solutions was measured at different time intervals. The swelling behavior was observed to be dependent on the degree of cross linking, concentration of chitosan and swelling environment. The structural and morphological studies of beads were carried out by using a scanning electron microscope (SEM).