Weak flexural properties of wood plastic composites(WPCs) limit their structural application. Recentlyinvestigation of nano particles looks promising to enhancebending properties of WPCs. In this study, the authors haveinvestigated the effect of different concentrations of nanoclay(modified montmorillonite) and coupling agent on themechanical and micro-structural properties of polypropylene/wood-fiber composites. We Bath internal mixer in certainprocessing conditions used for making the samples and then allsamples molded using injection molding for making samplesfor performing mechanical measurements. Samples preparedin four different concentration of nanoclay 0, 1, 3 and 5 wt%(total weight) and two different concentrations of maleicanhydride grafting (MAPP) 5 and 10 wt%. Mechanical resultsindicate that both flexural and impact strength of thecomposites increasing in sample containing 3% nano clay. Inother trend, Scanning Electron Microscope (SEM) imagesshow better interaction of wood fibers and polymer matrixwhen the authors added 5 wt% MAPP as coupling agent.