Abstarct: Natural fracture provides complex paths for fluid flow, and therefore affects reservoir characterization, reservoir performance and recovery factor. Studying and using fracture characteristics in reservoir is an important factor for optimizing reservoir performance. This study, addresses the issues of how to derive different information from various dynamic and static sources, analyzing these information and finally modeling natural fractures. Present study focused on one of the Iranian south carbonate reservoirs. This reservoir’s petrology consists of limestone, dolomite, anhydrite, and shale facies in reservoir laxyers of Dalan and Kangan formations. In this thesis stochastic discrete fracture network simulation approach is used for deriving 3D fracture models. In order to extract inputs for DFN modeling using this method some necessary analyses of the fractures is required. These analyses include fracture intensity calculation in wells, fracture aperture calculation, fracture orientation analysis, classification of fractures in fracture sets and analysis of these sets orientation, calculating density log in each well, calculating fractures density in each rock facies and also studying the role of each facies on fracturing. The Fullbore formation microimager (FMI) interpretations of three wells A, B and C, have been used in this study. Wells A, B and C were logged over the intervals from 2812m to 3297m, 2731m to 3226m and 2836m to 3286m, respectively. Also, for dynamic analysis of natural fractures, the dynamic data of four wells, D, E, F and G, have been used. Computed fracture intensities in wells, A, B and C were 0.22 (1/m), 0.29 (1/m) and 0.064 (1/m), respectively. Fractures aperture in all wells is also computed and the mean aperture in wells A, B and C is equal to 0.02 (cm), 0.01 (cm) and 0.23 (cm), respectively. Generally, fractures in all wells show dispersion in their strike and dip. In well A, the open fractures dip at an average inclination of 60 degree. They exhibit a dominant strike trend of N35E. In well B, open fractures dip at an average inclination of 62 degree and they show dominant strike toward N20E. Open fractures in well C dip at an average inclination of 65 degree and the main strikes are N35E and N35W. In order to categorize fractures, the orientation of total fractures in three wells is analyzed simultaneously and fractures are categorized into three sets. Fracture density for each well was computed and equals to 0.417, 0.519 and 0.347 respectively to well A, B and C, and for each facies it was computed and its value for limestone, dolomite, and anhydrite was 0.629, 0.457 and 0.127, respectively. And computed fracture density for shale was equal to zero. Dynamic analysis has been used for confirmation of fracture analyses. baxsed on dynamic analyses, the main contributor laxyers have more natural fractures. This result shows that fractures are distributed all over the reservoir especially in these laxyers. Finally, baxsed on mean value of extracted information in each well and fracture set, 3D fracture models using discrete fracture network approach were built.