Two totally waste products, agricultural residues and mixed plastic wastes collected from domestic and industrial sectors, are used in this study for the recovery of energy rich biofuel and value-added chemicals. The copyrolysis experiments using fixed bed reactor are conducted in order to analyse the synergetic effects. The experimental works are carried out with different proportion of mixed plastics blended with agricultural residues. The reaction temperature and biomass-to-waste plastics ratio on product distributions are studied and addressed. The thermogravimetric analysis conducted at different temperatures clearly distinguished the pyrolysis behaviours of biomass and plastics. The positive synergistic effects defined as higher yield of volatiles compared to predicted yield for bio-oil were identified at particular mixing ratio. Both biomass wastes and plastic wastes show optimal performance of 60.42 wt% oil yield at 60% addition of waste plastics. The oil products obtained under favourable conditions have a higher heating value compared to the oil obtained from biomass pyrolysis. The GC-MS study confirmed that the interaction between biomass and plastics during copyrolysis resulted in decreased oxygenated contents in the oil products.