Soil erosion and dust dispersion in the air, dust particle dispersion and particle displacement and their side effects are considered as one important environmental treats. There are various solutions for soil stabilization and preventing dust phenomena. One of the most conventional methods is soil stabilization using mulches more specifically oil mulches and biological struggle via planting different plant in dust producing sources which is used to prevent soil erosion specially wind erosions and soil stabilizing. In general the goal of using oil mulches is creation of adherence among soil particles especially sand particles and increasing stability against movement by the wind. The conducted researchwere performed in the form of complete random factorial tests in order to find the effect of oil mulches on soil characteristics, specially biological properties in Ahwaz region and under laboratory conditions. Four different zones with history of oil mulch application of 10, 20, 30 and 40 years were chosen. Besides, one region without application of oil mulch was considered as the control. The soil samples were taken from 2 depths including 0-30 and 30-60 cm and the samples were transferred to the laboratory. The results showed that oil mulches have significant effects on chemical and biological properties of the soil. In long term oil mulches increased soil organic carbon content,soil electrical conductivity, potassium and phosphorous contents, as well as microbial population and respiration. Furthermorethe pH, lime content, nitrogen content and cation exchange capacitywere relatively stable in longterm. Results also showed that oil mulches were gradually degraded and consequently enhancedmicrobial respiration and population. They had an important effect on soil enzyme activities. They increasedsoil catalase and lipase enzymes in contrary application of oil mulches causes the dehydrogenase and fluorescein diacetate hydrolytic activityenzyme of the soil to increase at the earlier ages and to stay stable after passing few years. As an overall conclusion it can be stated that oil mulches have significant and important effects on the soil biological properties which are reduced in time. It’s recommended to select and use environmental friendly mulches in order to decrease environmental side effects of oil mulches. Key Words: Soil erosion, Soil pollution, Oil mulches, Soil biological properties, Soil enzymes