In the last two decades, the new pollutants such as perfluorooctanoic acid (PFOA) and per-fluorooctane sulfonic acid (PFOS), which are harmful to human health, is one of the major challenges in the groundwater of metropolitan cities. In this laboratory-field-office research, nine pollution sites, landfill, wastewater treatment plant, industrial park, textile manufacturing company, metal plating workshop, two military barracks, and two fire stations were selected in Karaj. Three points for each location and a total of 27 groundwater sampling points were conducted. To calculate the concentration of PFOA and PFOS, the defluorination ratio was used. For this purpose, the fluoride ion concentration was calculated in the laboratory and based on it, the percentage defluorination curve, as well as the number of carbon-fluorine structures and placement in the formula, the concentration values of PFOA and PFOS were calculated. The results showed that the PFOA minimum and maximum ranged from 0.38 to 3.01 and PFOS from 0.33 to 2.63 micrograms per liter. Comparing contaminants with the American standard, with both contaminants of 0.004, and the European and World Health Organization with PFOA of 0.5 and PFOS of 0.1 micrograms per liter, shows an inappropriate situation. The lowest of PFOA and PFOS are found in landfills, textile factories, and metal plating workshops, and the highest are found in industrial estates, military barracks, and fire stations. According to the results, the construction of industrial estates and military barracks in Karaj and the direct transfer of fire station wastewater to the aquifer are not recommended.