Propolis is a resinous substance collected by honeybees from various plant sources, which largely define its chemical composition, particularly its phenolic constituents. Different types of propolis have been identified based on their phenolic profiles, such as poplar-type, rich in flavonoids like chrysin and pinocembrin; Brazilian green propolis, characterized by artepillin C and cinnamic acid derivatives from Baccharis dracunculifolia; Brazilian red propolis, distinguished by isoflavonoids and neoflavonoids from Dalbergia species; and Pacific-type, featuring phenolics from Macaranga tanarius. This chapter reviews the phenolic composition of these and other types of propolis—including flavonoids, phenolic acids, and other phenolic compounds—using data from advanced analytical methods like high-performance liquid chromatography-diode array detector-mass spectrometry (HPLC-DAD-MS) and gas chromatography-mass spectrometry (GC-MS). Furthermore, it examines the significance of phenolic markers in determining the botanical and geographic origins of propolis.