The aim of present study was to evaluate antioxidant efficacy of pussy willow extract (PWE) and essential oil (PWEO) in stabilization of sunflower oil (SFO) during ambient storage (60 days at 25°C). Initially, total phenolic (TP) and total flavonoid (TF) contents were evaluated. Then, PWE, PWEO, and TBHQ were added to SFO. Peroxide value (PV), carbonyl value (CV), total polar compound (TPC), acid value (AV), and Oxidative stability index (OSI) were measured every 15 days. The results showed that PWE had higher TP and TF than PWEO (TP: 966.72 mg GAE/g and 355.8472 mg GAE/g, respectively; TF: 619.45 mg/100 g and 195.45 mg/100 g, respectively). Furthermore, according to all stabilization parameters, PWE had higher antioxidant efficacy followed by TBHQ, PWEO, and control, respectively. Therefore, PWE has antioxidant activity and it may be recommended as natural strong antioxidants to suppress lipid oxidation.