Ninety patients with knee osteoarthritis (OA) were randomized to receive lavender oil (n=30), piroxicam gel (PG) (n=30), or paraffin placebo (n=30) applied daily for two months. The primary outcome was change in pain severity measured by the Visual Analogue Scale (VAS). Secondary outcomes included heel–thigh distance flexion, WOMAC pain, stiffness, physical function, and total WOMAC scores. Outcomes were assessed at baseline, one month, and two months. Overall, the results revealed that both lavender oil and PG significantly reduced VAS pain scores from baseline to one month, with no further significant improvement at two months, and no significant difference between the two treatments. Lavender oil provided pain and function improvement comparable to PG, suggesting it may be a safe, effective complementary option for knee OA symptom relief.