: The use of polymer blends in food packaging is developing. Due to their interstitial properties, these materials can cover a wider range of properties than pure polymers. One of the basic problems with the use of polymer blends, especially with an active agent as food shelf life durability, is the phase separation of these blends and the property loss of the final product, especially mechanical properties. One of the new methods to improve the compatibility of polymer blends is the use of nanoparticles. In this study, using Cloisite30B platelet nanoparticle in three components of 2.5, 4 and 6, attempts were made to improve the compatibility of tow common polymer in the packaging industry the LDPE/EVA blend with a ratio of 70 to 30. To investigate the compatibility effect of nanoparticle, scanning electron microscopy (SEM) test was used. Also, the mechanical properties of polymer films, which are very important, were studied. SEM results showed phase separation of the blend and the formation of matrix-droplet morphology even in the presence of nanoparticles. However, improvement of blend compatibility was observed in the presence of nanoparticles, especially in the combination of optimal 4% of nanoparticles. The results of the mechanical properties test also showed an improvement in tensile strength, tensile modulus and elongation at break in the presence of nanoparticles, which increased by 20, 28 and 47 percent, in the presence of 4% of the nanoparticles, respectively. According to these results, it can be stated that the presence of nanoparticles increases the compatibility of the two phases, and the best example of compatibility also contains 4% of nanoparticles.