The insulin-loaded low molecular water-soluble chitosan(LMWSC) nanoparticle was prepared by ion-complex to improve the efficacy of intravenous injection of insulin. The nanoparticles were characterized by FT-IR spectroscopy, particle size. The particle size distribution and zeta potential of the nanoparticies were determined using dynamic light scattering technique. Transmission electron microscopy (TEM) was also used to observe the morphology of the namoparticles. It was found that the namoparticies carried positive charges and showed a size distribution in the range of 230-580 nm.