Fungal disease infections attack on the agarwood-producing plant of Thymeleaceae family produce fragrant resin known as agarwood, aloeswood, Eaglewood, aloes, kalamabak or oudh depending on the region [1]. In Indonesia, this fragrant resin called gaharu. Products of gaharu has been known since the 3rd century for a religious ritual in China, perfume binder, cosmetic, aromatherapy, and medicine for human health. There are more than 26 species of agarwood-producing trees of the genus Aquilaria, Gyrinops, Aetoxylon, Wikstroemia [2]. Aquilaria beccariana is one plant that produce agarwood from Aquilaria genus. The use of agarwood is not limited to the resin alone. Overall plant parts such as leaves, stem bark, fruit, seeds, and roots of aloes have potential medicinal properties [3]. Several studies have shown activity of this plant as antioxidant [2] [3], analgesic, antipyretic, anti-inflammatory [4], antihyperglycemic [5], and antimicrobial [3]. In the Province of Central Kalimantan, Indonesia, agarwood leaves empirically used to lower blood glucose levels. A phytochemical study revealed that agarwood leaf contained alkaloids, saponins, phenolic, flavonoid and terpenoids [2]. Phenolic and flavonoids secondary metabolites in plant are responsible for antioxidant activity [6] [7]. Phenolic characterized with presence of phenol group, while flavonoid is a largest group of phenolic compounds in nature with C6-C3-C6 configuration [8]. Agarwood leaves commonly used by public without considering the age of leaves. Leaf buds of plant of tea are used because they contain the highest phenolic compounds. In most plants mature leaves were used because it contains more than 90% vacuole in cells. The vacuole is a place to store organic and inorganic materials. In the old leaves, the activities of leaf decrease because the aging process in leaves can reduce the content of secondary metabolites [9]. Based on this, supposedly there are variations in the levels of secondary metabolites on leaf based on its position in a twig. Variations can affect the levels of antioxidant activity, thus affecting the pharmacological effects. Several studies have demonstrated an association between phenolic, flavonoids content and antioxidant activity. Content of phenols and flavonoids in three plants is directly proportional to the antioxidant activity [10]. This study was focused on the total phenolic, flavonoid content and antioxidant activity of A. beccariana leaves extract on different leaf position in a twig. The purpose of this study was to determine the levels of total flavonoids, total phenolic and antioxidant activity from young leaves, mature leaves and old leaves in A. beccariana.