The present study examined the use of poly(vinyl alcohol) (PVA) as a compatibilizing agent between chitosan and Poly(lactic acid) (PLA). To obtain these blends, a new methodology with 2 steps were developed. In a first stage, PVA/chitosan blends are prepared by casting, thus chitosan, which is hardly melted, is dispersed in PVA witch is a thermoplastic component. In a second stage, PVA/chitosan witch has good chemical affinity become a thermoplastic blend that was incorporated in PLA matrix by melting mixing. Melting processing occurred in a twin-screw extruder at temperature profile of 130,130, 135, 140, 145°C and 80 rpm. Measurements of FTIR, DSC, DMA were performed to verify the degree of mixing, characterize the compounds and to acquire insights about thermal-mechanical behavior. FTIR analysis confirmed that PVA/chitosan was good interaction and two significant changes in IR specter was observerd; the decrease in the intensity of absorption bands at 3355-3300 cm-1 referent to the –NH and –OH of the chitosan and PVA and the shifting of absorption band at 1750 cm-1 referred of ester group of PVA. DSC analysis revealed that the presence of PVA/Chitosan phase in PLA results in changes in the crystallization upon heating of the matrix. The morphology of the blends evaluated by scanning electron microscopy revealed that PVA/chitosan were melted and well dispersed in PLA matrix. A reduction in mechanical properties as well as the darkening of the dispersed phase during drying, suggest that the presence of solvent waste are sufficient to promote matrix degradation during processing. However, the positive results in chitosan fusion and dispersing of this processing method is innovative and represents a major advance in the study of polymer blends from natural polymers processed by melt processing and have potential allowing dispersion of polymers with high polarity in another polyesters matrixes by melting process.