Soil pollution is one of the most important environmental issues in industrial and developing countries. Due to development of petrochemical, oil and gas industries large amount of oil pollutants are released into the soil. There are various physical, chemical and biological methods have been used for remediation of oil-contaminated waters and soils which have both advantages and disadvantages. In this regards, thermal methods are distinguished through high efficiency and short remediation time among other methods. Microwave (MW) irradiation, as a thermal method, has a high potential to remediate soils contaminated with organic pollutants (e.g. petroleum hydrocarbons). Since it’s necessary to use a fast and suitable approach to remediate oil polluted soils, this study was carried out to find MW irradiation effects on removal of total petroleum hydrocarbons (TPHs) and polycyclic aromatic hydrocarbons (PAHs) in oil polluted soils. Oil-polluted and non-polluted soil samples were taken at the depth of 0-20 cm from Tehran Oil Refinery. This study was done in two different parts. In the first part, soil samples were irradiated under different MW powers (770, 1250 and 1100 watt) and different periods of time (5, 10 and 15 min) and then hydrocarbon removal from soil was investigated. Furthermore, in order to optimize the oil removal process, the effects of soil moisture (1, 5, 10% w/w) and activated carbon (0, 2.5, 5% w/w) were also investigated. Optimization of oil removal process was determined using Taguchi method with orthogonal array (L9) and the highest signal to noise was considered as the highest efficient parameter. Besides, MW irradiation effects on some biochemical characteristics of soil (e.g. organic materials, microbial activity and respiration as well as bacterial population) were investigated. In the second part of the experiment, oil removal efficiency from soil polluted with different pollutants including crude oil, kerosene, heavy diesel and light diesel (5% w/w concentration) and also different concentrations of crude oil (1, 5, 10% w/w) was surveyed under MW irradiation considering the optimized conditions of the first part. Evaporated materials during all experiments were collected through a condenser attached to the MW instrument. Soil petroleum hydrocarbons were extracted using Soxhlet and pressurized liquid extractor in the first and second parts of the study, respectively. The concentrations of petroleum hydrocarbons in the first part were determined using gravimetric method and in the second part were measured using GC-FID and GC-MS instruments. Results of Taguchi approach showed that the optimized conditions of experiment were 1% w/w moisture, 15 min time, 5% w/w activated carbon and 1100 watt MW power. During the MW irradiation of soil samples, humidity, activated carbon content, irradiation power and time showed the highest effect on oil removal efficiency, respectively. Results revealed that TPH removal efficiency in contaminated soils having 5 and 10% w/w crude oil pollutant was up to 80%, whereas it was 100% in soils contaminated with 1% w/w crude oil. During the MW irradiation n-alkanes including C10-C25 and C25-C35 were dissipated. Petroleum hydrocarbons in soils containing kerosene were completely dissipated in soil after MW irradiation. The removal efficiency of PAHs having low molecular weight (e.g. benzene) was more than of compounds with high molecular weight (e.g. chrysene and pyrene) which could be related to their evaporation temperature. The highest and lowest PAH removal efficiency was achieved in MW irradiated soil having light diesel and kerosene, respectively. It’s concluded that MW irradiation is an efficient and fast approach to remediate soils contaminated with petroleum hydrocarbons. However, evaporation of pollutants and their transfer to the atmosphere, toxic byproducts and method application costs in field conditions should be considered. Keywords : Microwave, Soil pollution, TPHs, PAHs, Remediation