Ginseng, as a medicinal and edible plant, has ginsenosides as its core active components, which are widely applied due to their physiological functions such as antioxidant and anti-inflammatory activities; however, their structures and activities are easily affected by food processing. During processing steps such as cleaning, steaming/boiling, and fermentation, temperature, pH, and microbial enzyme systems alter the types, contents, and stability of active components through reactions such as hydrolysis and oxidation. The intrinsic linkage mechanism of "component transformation-activity-bioavailability" constitutes a core focus and challenge in current research. This study, based on spectroscopic techniques including high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), and liquid chromatography-mass spectrometry (LC-MS), systematically elucidates the mechanisms by which processing affects the active components of ginseng. Six categories of efficacy maintenance strategies, such as processing parameter optimization, microbial fermentation, and nano-delivery systems, are proposed, and a component-monitoring model for the processing procedure is established. On this basis, future key research directions and development trends in this field are further prospected.