Background: This study aimed to evaluate the bone mineral density (BMD), trabecular bone score (TBS), and fracture history of middle-aged patients hospitalized for heart failure (HF), as well as analyze the association of these factors with cardiometabolic parameters and muscle strength. Methods: A cross-sectional study with patients aged 40 to 64 years hospitalized for HF was performed. Dual energy X-ray absorptiometry was performed to obtain BMD and TBS. Fracture history, handgrip strength (HGS), and clinical and laboratory cardiometabolic parameters of the patients were evaluated. Results: Altogether, 109 patients were evaluated (female 50.5%). Medians and interquartile ranges for age and length of hospital stay were 58.0 (53.0–61.0) years and 20.0 (11.0–32.0) days, respectively. Osteoporosis was observed in 15.6% of the patients, low TBS was observed in 22.8%, and 6 patients had a history of fragile fracture. No differences between the sexes regarding BMD (p=0.335) or TBS (p=0.736) classifications were observed. No association was observed between low BMD and HF classification (p>0.05) regarding the ejection fraction, ischemic etiology, or New York Heart Association Functional Classification. However, there was a significant association between high serum parathyroid hormone (PTH) and the presence of osteoporosis (62.5 [37.2–119.0] pg/mL vs. 34.2 [25.0–54.1] pg/mL; p=0.016). There was a negative correlation between serum PTH and TBS (r=−0.329, p=0.038) and a higher frequency of reduced HGS in patients with low TBS (92.3% vs. 50.0%; p=0.009). Conclusions We found relevant frequencies of osteoporosis and bone microarchitecture degradation in middle-aged patients with HF, which were related to high serum PTH concentrations.