Nowadays, car accidents are one of the transportation problems around the world. Therefore, improving the safety attribute of the automakers products is the most important target in such companies. The real crash tests that are performed in the automotive testing companies are costly and time-consuming. For this reason, in the recent years, crash simulation using finite element method has been widely expanded. In this article, side crash behavior of one of Iranian automakers products named DENA is investigated numerically. In this way, the side panel of the DENA car is first meshed by HyperMesh software and then the side crash is simulated using finite element method in LS-DYNA software. In this regard, collision speed, vehicle connections, material definition, barrier model, and initial vehicle collision conditions are considered according to ECE R95. This article aims to evaluate the influence of the side impact pipe on the improvement of the side crash behavior of DENA car. Moreover, effects of replacing steel side impact pipe with the GFRP (Glass fiber reinforced polymer) composite one is investigated. The results show that by adding a composite pipe, the safety of the car in the collision is generally increased, and more energy absorption is created (about 10%). And as a result, the weight of the car and consequently the fuel consumption of the car is reduced.