2019 Medical Technologies Congress, TIPTEKNO 2019 --3 October 2019 through 5 October 2019 -- -- Pericardial fluid (PF) is located in the space between the heart and the pericardium surrounding the heart. PF contains mesothelial cells and leukocytes such as monocytes, lymphocytes, macrophages, and neutrophils. Mesothelial cells are similar to mesenchymal stem cells with their differentiation potential and characteristic features. The number of mesothelial cells not only increases with damage to the heart, but also secrete growth factors to support tissue repair. In this study, 1, 10, 20, 50 ng/mL vascular endothelial growth factor (VEGF) was added to the in vitro cultured cells isolated from bovine pericardial fluid. For this purpose, images of control and VEGF groups on the first, fifth and tenth days were examined by light microscope and it was concluded that 50 ng/mL VEGF is the effective concentration for pericardial fluid cells. 10ng/mL VEGF was determined as effective concentration according to the complexity of the image, skewness and complexity of the histogram. © 2019 IEEE. Firat University Scientific Research Projects Management Unit: FOA-2016-6692 ACKNOWLEDGEMENT This study was supported by Erciyes University Scientific Research Projects Coordination Project No; ÖNAP, FOA-2016-6692.