The study investigated the association between preoperative chronic pain and postoperative delirium (POD) in 200 elderly patients (mean age 69 years, ASA II/III) undergoing elective orthopedic surgery. POD occurred in 33% of patients (66/200) within 7 days after surgery, diagnosed by 3D-CAM method. Preoperative chronic pain (duration ≥ 3 months, assessed by VAS) was present in 58.5% of patients (117/200). Univariate analysis showed unadjusted OR = 2.039 (95% CI: 1.090–3.811), multivariable adjusted OR = 2.488 (95% CI: 1.282–4.8037, P = 0.0048). In patients with chronic pain, current pain intensity (VAS score) was associated with a higher risk of POD (OR = 1.858, 95% CI: 1.291–2.675, P < 0.001). Preoperative chronic pain increases the risk of POD in elderly patients after elective orthopedic surgery.