Being located on the Alpine-Himalayan belt, Iran is located in one of the most earthquake-prone places in the world. As it is clear in the zoning of the seismic maps of Iran, a large part of the country is in the relatively high-risk zone. From the published reports about Iran's earthquakes, it can be seen that the most type of these earthquakes are shallow crustal, which have always been more destructive. In such a situation, it is necessary to evaluate the vulnerability and seismic performance of existing buildings according to their importance and type of structure. For this reason, the evaluation of the seismic performance of buildings such as school buildings, which are among the most important buildings due to population density, is of great interest. For this reason, in this study the seismic fragility curves of reinforced concrete school buildings in Isfahan province are determined to investigate their seismic vulnerability. Based on existing school in Isfahan province, the structural types of the school building were moment reinforced concrete frames, steel frames and masonry buildings. The statistical document in Renovation and Equipping schools of Esfahan organization shows that the most structure types were reinforced concrete structures. These buildings were designed based on different editions of standard 2800 in areas with different seismic risk and have different number of floors. The selected buildings of schools were divided into 14 general categories in terms of height, revision of design regulations, seismic risk and land type. In order to evaluate the vulnerability of selected buildings, incremental dynamic analysis (IDA) was performed using 22 far fault accelerograms as well as 12 near field accelerograms on two-dimensional frames in OpenSees software. The accelerograms were recorded on soil with site class D based on NEHRP. The nonlinear behavior of concrete and steel bars were modeled using concrete02 and steel02 models respectively, available in OpenSees. Moreover, the P-Delata effects were considered in the 2-D frame models by using leaning column available in the software. After calculating IDA curves, the seismic fragility curves were produced by considering the spectral acceleration in the main period of oscillation with 5% damping as the intensity measure and the maximum inter-floor drift as the failure index. It should be noted that log-normal distribution was using to determine fragility curves. The results showed that as the height of the structure increases, the fragility or vulnerability of the structures increases. Also, the probability of building collapse in areas with moderate seismic risk is higher than in areas with high relative risk. Moreover, according to the fragility curves It can be concluded that the one-story school buildings in high and moderate categories which had designed with third edition of Iranian seismic code (standard 2800) have lower priorities for strengthening.