Objective To explore the expression level and diagnostic efficacy of plasma D-dimer (DD) and fibrinogen (FIB) in hyperfibrinolysis of elderly patients with bleeding after benign prostatic hyperplasia (BPH) surgery. Methods 70 elderly BPH patients with postoperative hemorrhage and hyperfibrinolysis in our hospital were included into the observation group, and 75 elderly BPH patients with postoperative hemorrhage without hyperfibrinolysis were included into the control group. The serum levels of DD and FIB in the two groups of patients were compared, and the correlation of DD and FIB with clinical features and the diagnostic value of DD and FIB. Results Elderly BPH patients with hyperfibrinolysis showed significantly higher levels of DD and FIB than those without hyperfibrinolysis (P < 0.01). The increase in DD and the decrease of FIB were significantly correlated with the prolonged hospital stay and intensive care unit (ICU) monitoring (P < 0.05). The combination of DD and FIB showed high diagnostic value for postoperative hemorrhage with hyperfibrinolysis (AUC = 0.998). Conclusion The combination of plasma DD and FIB effectively and accurately diagnoses postoperative hemorrhage with hyperfibrinolysis. High levels of DD and FIB indicate prolonged hospital stay and postoperative ICU monitoring of elderly BPH patients with hyperfibrinolysis.