Aims: 1. To study the clinicopathological features of Gastrointestinal stromal tumors (GISTs). 2. To study and confirm the diagnosis GISTs by Immunohistochemistry and to establish the correct final diagnosis to help treatment of patient. Methodology: Thirty one cases of GISTs were diagnosed between January 2010 to October 2015. Their clinical presentations, gross and microscopic features were studied. The surgical specimens were categorized into risk groups based on the National Institute of Health (NIH) consensus criteria. Immunohistochemcal study was done on formalin fixed, paraffin embedded tissue blocks with a panel of five antibodies; CD-117, CD-34, SMA, Desmin and S-100. Result: __ampersandsignbull; Peak age of occurrence was between 5th and 7th decade. More cases were diagnosed in males than in females. __ampersandsignbull; Pain in abdomen was the most common presenting complaint. __ampersandsignbull; Small intestine was the most common site followed by stomach, colon and rectum. There were 16.1% cases of EGISTs (extragastrointestinal stromal tumors). __ampersandsignbull; The size of tumor as measured by the maximum diameter ranged from 2.5-30 cm. Average size was maximum for EGISTs. __ampersandsignbull; Based on the National Institute of Health (NIH) consensus criteria 60.9% (n=14) of cases belonged to the high risk group. 21.7% (n=5) were in the low risk group while 17.4% (n=4) belonged to intermediate risk group. __ampersandsignbull; Spindle cell type was the most common histological type (90.3%). __ampersandsignbull; Immunohistochemistry was done in all the cases and 90.3% (n=28) of cases were CD-117 positive. 35.5% (n=11) were positive for CD-34. Conclusion: Gastrointestinal stromal tumors (GISTs) are rare tumors of the GI tract and account for only 0.1-3% of the gastrointestinal neoplasms. Mitotic rate and tumor size have gained the greatest acceptance as being predictive of outcome. The role of Immunohistochemistry is well known in the diagnosis of GISTs and there has been continuing attempts at finding a more specific and sensitive marker than CD117. New markers like PDGFRA, PKC __ampersandsigntheta; and DOG1 are being analyzed. The combination of a detailed histopathological examination and Immunohistochemistry is important for diagnosis, management and prognostication of patients of GISTs.