In this study, co-pyrolysis of plastic wastes; polyvinyl chloride (PVC) and polyethylene terephthalate (PET) with different agricultural wastes such as cotton stalk, hazelnut shells, and sunflower residues near an arid land plant Euphorbia rigida was investigated. Thermal behaviors of raw materials were investigated by using thermogravimetric analyzer. Experiments were conducted at a heating rate of 10 degrees C min(-1) from room temperature to 800 degrees C in the presence of N-2 atmosphere with a flow rate of 100 cm(3) min-1. In the light of the experimental results, an appropriate temperature for the fixed-bed pyrolysis of biomass-plastic mixtures at (1/1, w/w) was determined and the raw materials were pyrolyzed at the same conditions except until the final temperature of 500 degrees C. Solid product (char) and liquid product (tar) of the pyrolysis were characterized by using different types of characterization techniques. Pyrolysis experiments showed that mixing by biomass and plastic materials had a positive effect on the liquid and gas yields. In addition, the characterization studies showed that biomass and plastic materials could be used to convert into valuable chemicals. (C) 2014 Elsevier B.V. All rights reserved.