The widespread use by young people of modern communication devices such as mobile phones means that they are particularly exposed to electromagnetic fields (EMF) and other problems. However, few studies have researched the effects of long-term exposure to EMF in the kidney. We therefore investigated oxidative stress and apoptosis in long-term exposure to 2100megahertz (MHz) in a rat model. Twenty-four Sprague Dawley rats were divided into a control group (n=8, no EMF exposure), a group exposed to 2100MHz for 6h for 30d (n=8), and a group exposed to 2100MHz for12h for 30d (n=8). Immunohistochemical analysis was performed, using caspase-3 to evaluate apoptosis. Immediately after treatment, reduced glutathione (GSH), malondialdehyde (MDA) in kidney tissue and serum levels of various biochemical compounds were measured to detect oxidative stress. Deterioration was observed in the brush border in renal tubules of the EMF groups. The results of the immunohistochemical analysis revealed a greater number of positively stained renal tubular epithelial cells in the EMF groups as compared with that in the control group. In the EMF groups, renal MDA levels increased, and renal GSH levels decreased compared with those in the control group, as shown by a biochemical examination (p=0.00 and p=0.00, respectively). The findings showed that exposure to 2100MHz for 6 and 12h induced oxidative stress-mediated acute renal injury, depending on the length of exposure and dosage.