Boesenbergia pandurata Roxb. Schlecht. (Zingiberaceae), called ``Ngai bun'' in Viet Nam, is one of the Southeast Asian medicinal plants and its rhizomes are used primarily as a spice. This is a perennial, short-stemmed plant, formed by leaf sheaths and can grow up to 50 cm. The leaves are 7-11 cm wide and 25-50 cm long. Its rhizome surfaces are light brown in color, the inner rhizome is yellow, oval-shaped, and has a very aromatic odor. In folklore, Boesenbergia pandurata rhizomes are used as a spice for food processing. This plant contains pinostrobin as the major constituents. Previously showed that pinostrobin compound is the main ingredient together with a variety of biological activities such as antibacterial, inhibition of free radicals, ... Pinostrobin is necessary composition for the screening, testing, and quality evaluation of the rhizomes of B. pandurata species and others in the Zingiberaceae family. This research had conducted a reference standard of pinostrobin isolated from the rhizomes of B. pandurata had 99.26 % purity, which is reliable in medicinal testing. An HPLC method for pinostrobin determination was conducted and The quantitative HPLC analysis was validated for system suitability, selectivity, linearity ranges, and precision. Application of the process to investigate the preparation of extract shown that reflux extraction with ethanol obtained the highest pinostrobin content with 22.05 % in extracts and 2.89 % in dried rhizomes of B. pandurata.