We evaluated whether modified Model for End-Stage Liver Disease (MELD) scores are useful for predicting the postdischarge prognosis in hospitalized patients with heart failure (HF) who are discharged alive. The MELD-XI and MELD-Na scores were calculated at discharge for a total of 1156 patients in the HIJ-HF II study. We also studied 3 groups on the basis of the left ventricular ejection fraction (LVEF): the HFrEF (LVEF < 40%), HFmrEF (LVEF 40–49%) and HFpEF (LVEF ≥ 50%) groups. The primary outcome was all-cause mortality, and the secondary outcome was rehospitalization due to worsening HF. The median MELD-XI and MELD-Na scores were 12 and 14, respectively. After a median follow-up of 19 months, there were significantly higher rates of all-cause mortality in patients with MELD-XI scores ≥ 12 than in those with MELD-XI scores < 12; there were also higher rates of all-cause mortality in patients with MELD-Na scores ≥ 14 than in those with MELD-Na scores < 14 (both log-rank p < 0.001). The cumulative incidence function based on a competing risks model showed a higher rate of rehospitalization due to worsening HF in patients with MELD-XI scores ≥ 12 than in those with MELD-XI scores < 12 and a higher rate of rehospitalization due to worsening HF in those with MELD-Na scores ≥ 14 than in those with MELD-Na scores < 14 (both Gray’s test p < 0.001). The adjusted hazard ratios (HRs) of all-cause mortality for patients with MELD-XI scores ≥ 12 and those with MELD-Na scores ≥ 14 were 2.07 [95% confidence interval (CI) 1.25–3.44] and 2.79 [95% CI 1.63–4.79], respectively, in the HFrEF group; however, the HRs were not significant in the HFmrEF or HFpEF groups. Thus, MELD-XI and MELD-Na scores may be useful for predicting prognosis in hospitalized HF patients who are discharged alive, especially for those in the HFrEF group.