Alpinia galanga (L.) Willd. and Alpinia officinarum Hance, commonly known as greater galangal and lesser galangal, respectively, belong to the family of Zingiberaceae (ginger). Due to their spicy flavor and aromatic odors, both of the two rhizomes have long been used as flavoring ingredients and spices in Asia. They also were well-known traditional Chinese medicine and have been widely used as a remedy for gastrointestinal diseases, such as stomachache, dyspepsia, and gastrofrigid vomiting. Previous phytochemical investigations have shown that they have some similar chemical constituents, such as diarylheptanoids, flavonoids, volatile oil, terpenes, phenylpropanoids, and glycosides, but the main chemical components are different. A. galanga is rich in a variety of phenolic compounds and essential oils, whereas A. officinarum is rich in flavonoids and diarylheptanoids. Investigations have shown A. galanga and A. officinarum have many biological activities, including effectiveness as antiinflammatory, antitumor, antiviral, antimicrobial, antioxidant, antiallergic, and gastroprotective agents. This chapter will give an exhaustive review of the botanical properties of these plants. In addition, the phytochemical and pharmacological properties and the adulterant identification of these two plants will also be discussed.