Background: While it is well known that cyclooxygenase-2 (COX-2) expression is increased in colorectal adenoma and carcinoma, there is only limited information on its status in stromal tumours. Methods: Immunohistochemical COX-2 staining was performed on a total of 42 confirmed gastrointestinal stromal tumours (GISTs) in the Pathology Department of Gaziantep University and the findings were compared with various other parameters. Results: We found a statistically significant correlation between the tumor mitosis and COX-2 expression in GISTs. However, there was no relationship between COX-2 expression and death rate, presence of metastasis, tumour size, risk staging, usage of tyrosine kinase inhibitors, and complete resection rate. Conclusions: In the light of these findings, the usage of COX-2 inhibitors with or without tyrosine kinase inhibitors in GIST patients may be helpful in the adjuvant setting to prevent or delay recurrence. Moreover, we need more studies to define the status of COX-2 inhibitors in GISTs.