Almond (Al) (Prunus dulcis, belongs to the family Rosaceae) green hulls are waste materials that are generated annually in the almond harvest and recently have received increasing attentions owing to their antioxidant properties. The phenolic and flavonoids compounds were extracted from almond hulls under reflux condition at 50 ˚C using acetone as a solvent. Total phenolic and flavonoid content were 81.0 mg GAEs/g extract and 55 mg catechin/g extract which were determined by Folin– Ciocalteu colorimetric method and the aluminium chloride colorimetric method, respectively. The antioxidant property of extract was evaluated by DPPH assay. Almond hull extract demonstrated a concentration dependent scavenging activity by quenching DPPH radicals with SC50 value of 25 μg/ml which was compared with ascorbic acid as positive control (SC50 0.03 μg/ ml). In order to determine the type of phenol and flavonoid compounds, gas chromatography/mass spectroscopy (GC/MS) analysis was performed. According to the results obtained from GC/MS analysis, almond extract contains ferulic acid, p-coumaric acid, quercetin, mequinol, sinapinic acid, catechin and homovanillic acid. Regarding the high phenolic content of almond hull extract and its great antioxidant property it could be used for treating of oxidative stress-related diseases.

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