The Yangjiazhangzi molybdenum orefield is located in the central area of the known Bajiazi-Yangjiazhangzi magmatic-hydrothermal mineralization belt. Based on the regional geological characteristics, metallogenic geological background and deposit geology of the orefield, the molybdenum deposits in Lanjiagou, Yangjiazhangzi and Beisongshumao are researched in detail. The genesis of the deposit is redefined with the mineral sources, ore-forming temperature and metallogenic epoch. A regional metallogenic model is established accordingly. Finally, the geological, geophysical and geochemical prospecting marks for molybdenum deposits in Yangjiazhangzi area are summarized.