Purpose: Pain or discomfort caused by foot diseases may lead to abnormal gait, resulting in decreased bone mineral density (BMD) of the affected lower limb. We analyzed the effect of foot affection to BMD and its clinical significance. Materials and Methods: Bilateral hip BMD was evaluated in 93 patients with unilateral chronic foot disease. To minimize statistical errors, we excluded patients with medical histories that had influence on BMD. Analysis was based on the results of BMD tests at the first visit. All patients denied past medical intervention for osteoporosis. The difference in density between bilateral limbs was determined by comparing BMDs of the neck, upper neck, trochanter and total area of hip. Results: Test results revealed the decrease of BMD in the lower limb with the affected foot, compared to the unaffected side. This decrease was significant in the area of the trochanter (p <0.05). There was no marked difference of BMD in relation with duration of affection, underlying disease or age. Pertaining the location of foot affection, the hindfoot group showed significant decrease in BMD compared to the forefoot group. The group with affection in bone and joint also showed a marked decrease in BMD compared to the soft tissue group (p <0.05). Conclusion: Pain and discomfort caused by chronic foot diseases can lead to a decrease in the BMD of the affected lower limb. This may increase the risk of complications such as osteoporotic fracture and muscular atrophy.