: Due to environmental issues starch could be an appropriate alternative for film and foam.Starch is obtained from renewable resources, inexpensive and can be found in abundance.Unfortunately starch has some disadvantages. It is highly hydrophilic, it has brittle behavior without plasticizer, andits mechanical properties are very sensitive to moisture. Few approaches for overcoming these disadvantages have been proposed. Blending starch with suitable biodegradable polymers and additionof anofibers to starch can be considered. High specific surface area,aspect ratio andstrength and flexibility are characteristics of microcrystalline cellulose fibrils. In this study, the cellulose nanofibers were extracted from wheat straw and used as reinforcing materials in foam production. Combination of chemical and mechanical methods were used to extract cellulose nanofibers.In orderto remove lignin and hemicellulose chemical steps were designed.A supergrinder was used to isolate nanofibers. In this process, a slurry of microfibers was passed through a gap between fixed and rotate grinder stones. Freeze-drying method was employed for foam production.First suspension of starch in water was prepared and then different percentages of nanofibers (0,10,20,30% wt) with 3% glycerol as plasticizer were added to the mixture.In order to gel starch, this suspension was stirred at a temperature of 90°C for 30 min by a mechanical stirrer. To complete the gelatinization process, the mixture is poured into a Petri dish for 24 h at a temperature 4°C is placed. This gel was frozen at a temperature -80°C and thenplaced into the freeze dryer for 48 hours. To determine the chemical composition of the fiber constituents (cellulose, hemicellulose and lignin) NREL / TP - 510-42618 was used. The results showed that amount of cellulose after chemical processing has increased from 40% to 90%. Morphological changes during the process of chemical fibers was showed that the fiber diameterswas reduced. Fibers diameter distribution from SEM images was determined to be 70-90 nm. Peaks observed in the FTIR spectroscopy confirmed the removal of lignin and hemicellulose. Adding nanofibers leading to the formation of uniform cellswith small diameters. Adding nanofibers by 20 wt% increased the composite modulus and compressive strength of the foam. Water absorption and diffusion coefficient of foams decreased with increasing cellulose nanofibers. Key words: Wheat straw, nano fibers, cellulose, starch, foam