Purpose Osteoporotic vertebral compression fractures (OVCFs) have a serious impact on people’s health and quality of life. The purpose of this study was to analyze brain volume in patients with osteoporosis using brain magnetic resonance imaging (MRI) and to investigate the relationship with osteoporotic vertebral compression fractures. Materials and methods We included 246 patients with osteoporosis who underwent thoracolumbar radiographs and brain MRI at our hospital. Clinical data on age, sex, bone mineral density, height, weight, osteoporosis medication, hypertension, diabetes, alcohol drinking, and smoking were collected. Intracranial cavity, brain parenchyma, and lateral ventricles volumes were measured using brain MRI with a semiautomated tool. Results We founded an independent correlation between age and volume percentages of the brain parenchyma and lateral ventricles. We observed a statistically significant decrease in volume percentage of the brain parenchyma and an increase in volume percentage of the lateral ventricles with increasing age. In addition, we confirmed that patients with OVCF showed a significantly lower volume percentage of brain parenchyma than patients without OVCF. Conclusion We observed a significant association between OVCF and volume percentage of brain parenchyma. Degeneration of the brain may lead to a high incidence of falls, and OVCF may occur more frequently in patients with osteoporosis.