Objective To observe the effects of goal-directed fluid treatment on circulatory status, immune inflammatory response and early cognitive function in elderly patients undergoing total hip arthroplasty. Methods Sixty elderly patients undergoing total hip arthroplasty were randomly divided into three groups: restricted fluid treatment group (R group), open fluid treatment group (L group) and goaldirected fluid treatment group (G group)，20 cases in each group. Mean Arterial Pressure (MAP） and (lactic acid)Lac values were recorded before anesthesia induction (T1), 1h at the beginning of surgery (T2), immediately after surgery (T3), and at Postanesthesia care unit (PACU) exit (T4). Venous blood was collected 1d (T0) before surgery, 1 (T5), 3 (T6), and 7d (T7) after surgery to measure the concentrations of inflammatory factors and brain injuryrelated proteins, and evaluate the cognitive function of the patients. Results The total amount of liquid, crystal and colloid in G group was higher than that in R group, but lower than that in L group (P＜0.05). At T2 and T3, The MAP of G group was higher than that of R and L groups (P＜0.05). At T2, T3 and T4, Lac value in group G was lower than that in groups R and L (P＜0.05). At T5, T6 and T7, serum levels of TNF-α, IL-1β, IL-6, S-100β and Tau protein in G group were lower than those in R and L groups, and mini-mental state examination (MMSE) score was higher than that in R and L groups (P＜0.05). Conclusion Targetdirected fluid therapy is more effective in maintaining hemodynamic stability, alleviating postoperative inflammatory response and reducing the risk of early postoperative cognitive dysfunction in elderly patients undergoing total hip arthroplasty.