Although heart failure (HF) and osteoporosis are common diseases, particularly in elderly populations, patients with HF have an increased risk for osteoporosis. The relationship of HF with osteoporosis is modified by gender and the severity of HF. In addition, shared risk factors, medication use, and common pathogenic mechanisms affect both HF and osteoporosis. Shared risk factors for these 2 conditions include advanced age, hypovitaminosis D, renal disease, and diabetes mellitus. Medications used to treat HF, including spironolactone, thiazide diuretics, nitric oxide donors, and aspirin, may protect against osteoporosis. In contrast, loop diuretics may make osteoporosis worse. HF and osteoporosis appear to share common pathogenic mechanisms, including activation of the renin-angiotensin-aldosterone system, increased parathyroid hormone levels, and/or oxidative/nitrosative stress. HF is a major risk factor for mortality following fractures. Thus, in HF patients, it is important to carefully assess osteoporosis and take measures to reduce the risk of osteoporotic fractures.