The effects of pretreatment of coir fiber for manufacturing coir-based green composites have been studied. Composites were prepared using coir fiber treated with varying pretreatment condition. The process ability conditions and physical, mechanical and thermal characteristics of these composites were analyzed. The changes in morphological properties with different coir pretreatment condition were discussed. Surface characterizations of the unpretreated and pretreated coir fiber were investigated from scanning electron microscopy (SEM) studies. It revealed that there is an improved adhesion between fiber and matrix in the case of pretreated coir. SEM investigations confirm that the increase in properties is caused by improved fiber-matrix adhesion.