Caveolin-3 (CAV3) is a muscle-specific protein present within the muscle cell membrane that affects signaling pathways, including the insulin signaling pathway. A previous assessment of patients with newly developed type 2 diabetes (T2DM) demonstrated that CAV3 gene mutations may lead to changes in protein secondary structure. A severe CAV3 P104L mutation has previously been indicated to influence the phosphorylation of skeletal muscle cells and result in impaired glucose metabolism. In the present study, the effect of CAV3 K15N gene transfection in C2C12 cells was assessed. Transfection with K15N reduced the expression of total CAV3 and AKT2 proteins in the cells, and the translocation of glucose transporter type 4 to the muscle cell membrane, which resulted in decreased glucose uptake and glycogen synthesis in myocytes. In conclusion, these results indicate that the CAV3 K15N mutation may cause insulin-stimulated impaired glucose metabolism in myocytes, which may contribute to the development of T2DM.