Objective To investigate whether predicted heart mass (PHM) ratio can predict the prognosis of adult heart transplant patients. Methods Clinical data of 309 heart transplant patients in Zhengzhou Seventh People's Hospital from May 2018 to July 2024 were retrospectively analysed. The cut-off value of the PHM ratio was calculated, grouping was conducted according to the truncation value, and the baseline data and prognosis data of the two groups were compared. Results A total of 236 adult heart transplant recipients were included in this study according to the inclusion and exclusion criteria. Cut-off value of the PHM ratio was –0.01. There wer 63 patients in the PHM ratio>–0.01 group and 186 patients in the PHM ratio ≤–0.01 group. The results of univariate analysis revealed that there were statistical differences between the two groups in terms of recipient gender (P<0.001), donor gender (P<0.001). There was no statistical difference in primary disease, recipient blood type, infectious disease, emergency status, preoperative intra-aortic balloon pump (IABP), preoperative extracorporeal membrane oxygenation (ECMO), preoperative continuous renal replacement therapy, preoperative mechanical ventilation, and preoperative blood creatinine (P>0.05). In terms of prognosis, there were statistical differences between the two groups in postoperative ECMO (P=0.043), and postoperative IABP (P=0.006). Survival rate was significantly lower in the PHM ratio ≤ –0.01 group than in that in the PHM ratio>–0.01 group (HR=1.748, 95%CI 1.007-3.035, P=0.047). Multifactorial Cox regression showed that PHM ratio was significantly associated with survival after heart transplantation (HR=0.000 3, 95%CI 0.000 1-0.001 2, P<0.001); recipient sex, donor sex, donor BMI, donor BSA, recipient BMI , recipient BSA did not significantly correlate with post cardiac transplantation survival. Conclusion Predictive heart mass ratios can predict the prognosis of adult heart transplantation, and donor hearts with PHM ratios>–0.01 should be selected as much as possible when performing heart donor evaluation.