Dexamethasone, with its anti-inflammatory properties, has a wide range of applications in medicine and is now used in protocols for differentiation of mesenchymal stromal cells. Its impact on the growth and differentiation of various cell types has been the subject of research for many years. Due to the relatively limited number of studies on the effects of dexamethasone on C2C12 cells, the aim of this study was to determine the influence of different concentrations of dexamethasone on their growth and differentiation. During the experiment, cells were treated with dexamethasone at concentrations of 100 and 200 µM, and its effects on the growth and differentiation of C2C12 cells were monitored for 168 hours. The cell count was determined using the trypan blue method, cell differentiation was observed through microscopic staining with crystal violet and the data were statistically analyzed. The results showed that the number of cells treated with 100 µM dexamethasone increased by 10.14% after 48 hours and by 2.97% after 96 hours compared to control cells. On the other hand, treatment of cells with 200 µM dexamethasone resulted in a decrease in the number of cells by 24.32% after 48 hours, and a decrease of 5.41% after 96 hours compared to control cells. Morphological characteristics showed that C2C12 cells treated with dexamethasone appeared narrower and elongated compared to control cells. Individual differentiated myotubes could be observed in all cell samples, although even the control cells did not undergo complete differentiation into myotubes. Since the obtained results deviate to some extent from the literature data, further research is needed to determine the effects of dexamethasone on the growth and differentiation of C2C12 cells.