Abstract: Background　Under the dual impetus of accelerating global population aging and iterative advances in hepatobiliary surgical technology, the number of elderly patients undergoing liver cancer surgery continues to rise. Aging leads to multi-system functional reserve decline in elderly liver cancer patients, compounded by chronic comorbidities, leaving most of them in a state of frailty before surgery. Frailty not only interferes with postoperative recovery and affects prognosis but also increases medical resource consumption. Therefore, early identification and intervention for frailty in elderly liver cancer patients are crucial. Objective　To investigate the prevalence and influencing factors of preoperative frailty in older patients with liver cancer, and analyze its association with hospital length of stay. Methods　This multicenter retrospective study included patients aged ≥60 years scheduled for elective surgery for liver cancer in the hepatobiliary surgery departments of three tertiary hospitals in Beijing from April to September in 2025. Demographic and clinical data were collected. Frailty was assessed using the Fried Frailty Phenotype. Logistic regression was used to identify factors associated with frailty, and Gamma regression was used to examine the association between preoperative frailty and length of hospital stay. Results　A total of 367 patients were included, with a mean age of (66.5± 5.7) years; 272 cases were male (74.1%). Preoperative frailty was identified in 119 patients (32.4%). Logistic regression analysis found that malnutrition (OR=11.810, 95%CI: 3.523 - 45.930, P＜0.001), age increase (OR=1.158, 95%CI: 1.048 - 1.291, P=0.005), and multiple previous surgical histories (OR=7.442, 95%CI: 2.146 - 28.838, P=0.002) were independently associated with an increased risk of preoperative frailty, while daily exercise (OR=0.028, 95%CI: 0.006 - 0.105, P＜0.001) and higher albumin levels (OR=0.884, 95%CI: 0.791 - 0.974, P=0.018) were independently associated with decreased risk. The median total length of stay was 14 days (IQR: 11-18 days) in the frailty group, significantly longer than 10 days (IQR: 8-13 days) in the non-frailty group (P＜0.001); the preoperative preparation time was 6 days (IQR: 5-8 days) vs 5 days (IQR: 3-7 days, P＜0.001); and the postoperative length of stay was 7 days (IQR: 4-10 days) vs 5 days (IQR: 4-7 days, P＜0.001). After adjustment for age, sex, comorbidity number, Child-Pugh class, previous surgical history, and AFP level, multivariable Gamma regression showed that frailty status was independently associated with longer total hospital stay (RR=1.408, 95%CI: 1.282 - 1.547, P＜0.001), preoperative preparation time (RR=1.288, 95%CI: 1.143 - 1.451, P＜0.001), and postoperative stay (RR=1.522, 95%CI: 1.324 - 1.750, P＜0.001). Conclusion　 The prevalence of preoperative frailty is high in older patients with liver cancer, and preoperative frailty is independently associated with prolonged length of hospital stay. Therefore, it is recommended to incorporate frailty screening into preoperative assessment. Early identification and management of frailty and related risk factors may help reduce hospital length of stay and support more efficient use of healthcare resources, potentially improving perioperative recovery and outcomes.