Osteoporosis is a systemic and metabolic bone disease. New drugs with good curative effect, fewer side effects, and high safety need to be developed urgently. Recently, simvastatin has been used to treat osteoporosis more frequently; however, its clinical effect and treatment mechanism are still unknown. With the use of animal models, the treatment effectiveness of simvastatin on experimental osteoporosis was investigated and the functional mechanism was preliminarily explored. The results show that simvastatin significantly increased the mechanical parameters such as maximum load, stiffness, and energy-absorbing capacity, and improved the microarchitecture. They indicated that the antiosteoporosis activity of simvastatin may be due to the promotion of proliferation and differentiation of osteoblasts. Simvastatin was effective in treating experimental osteoporosis. This study provides necessary experimental evidence for the clinical application of simvastatin in osteoporosis treatment.