Minor ginsenosides are a class of processed saponins with minor natural content, high bioavailability, and outstanding bio-logical activity, which are usually obtained by biological or chemical transformation of prototype saponins directly extracted from Panax plants. In recent years, with the clarification of the biosynthetic pathway of saponins and the development of synthetic biology, it has become possible to use synthetic metabolic engineering methods with microorganisms as hosts to produce saponins. Minor ginsenosides have received widespread attention because of their remarkable biological activities in enhancing the immune function of the body and antitumor property. At present, most of the reviews on minor ginsenosides focus on transformation preparation, process optimization, and pharmacological activity, but there are some deficiencies in industrial analysis. This study summarized structural types, pharmacological activities, sources of acquisition, and transformation pathways of minor ginsenosides based on the relevant literature in China and abroad, proposed problems in the preparation of existing minor ginsenosides, and discussed the future research and utilization prospects, to provide a theoretical basis for improving the basic research of minor ginsenosides and promoting their industrialization.