Abstarct: The study area, northwest of Shahrood, is a part of south margin of the eastern Alborz. Stratigraphic studies illustrates that there are outcrops of Mesozoic and Cenozoic rock Units in this area with northeast-southwest to east-west structural trend. Geomorphologic View of the studied area is highly affected by Structural features such as folds and faults and karst features as well as lithology. During the field operations, the axial position was obtained for the Tepal N62E / 85NW and for the Teplal anticline N54E / 84NW. Also, according to Fleuty (1964), the anticline and syncline Tepal classified is totally open fold baxsed on the interlimb angle of fold Fleuty classification (1964) and baxsed on the dip of axial plane and plunge of hinge line , the folds are classification horizontal Upright & Gently plunging. The study of the two main Northwest Tepal faults (N53E/79NW) and South (N74E/66NW) indicates a left lateral strick slip mechanism for the Northern Tepal and the left lateral for the Southern Tepal. In this area strick slip faults localy have been seen NW-SE and NE-SW. Fracture analysis have been done in 12 stations. Finally, with regard to the genesis associated of these fractures associated with Tepal Folding, were classified in the category with folding.Most Fractures trending NW-SE and NE-SW set. Four main categories of fracture in the shear and tensile is detectable with nature. A- Fractures with an average position (N09E/75SE), B- Fractures with an average position (N35W/77SW), C- Fractures with an average position (N17W/67SW), D- Fractures with an average position (N54W/63SE). In order to describe the anticline and syncline Tepal with the main joints, observations were made on the fold and position of the fold axis was determined at (anticline)11/049 and (syncline) 17/062. baxsed on the position of the joints, the longitudinal, transverse, and shear fractures are recognizable in these stations relative to the folds axis. According to the descxription of the joints, the laxyers of most of the levels are classified in the category of joints and slopes. The classification of joints in formations includes four series with medium position, N32W/ 58SW, N44E/35SE, N41E/32NW, and N17E /63SE for Delichay Formation, Lar Formation, five series with a mean N21W/57NE, N04E/68N, N25W/81SW, N64E/83NW and N86W/67SW. For the Cretaceous lime N15E/81NW, N56W/72SW, N02W/76SE, N34W/70NE, for four fajan formations, the N49E/62SE, N23W/67SW, N08E/69NW and N71E/62SE, and Ziarat Formation of four junction formations with a mean position of N38W/71NE, N49W/67SW and N81E/75SE, and the fourth class divider divided into two categories N07E/68SW and N11W/81SW. The comparison between the junctions taken from each foemation was determined baxsed on the basis of the highest number of fractures in the limestone kretase and lar limestone formations. Finally, it was determined that, in addition to the effect of the distance between tectonic structures on the frequency of the junctions of the laxyers, it was also effective on the frequency of the junctions. Of the most important cases in the region, in Karst develop. According to the vastness of outcrop and fractures and joints existing in erea, Solutional cavities, Dry valleys, Karen’s and cave, karst accidents numerous including can be observe indicating dvelope karst in the study area.The slope of most joints is high indicating their importance in creating solutinal cavities as well as Karens. These joints transfer superficical waters into ground carry them to under ground canals. The most of joints turned into joints karens which can be seen abundantly in kretace limestones.