Abstract: The Beiya gold deposit is located in southwest Sanjiang alkali porphyry belt with complex geological structure, welldeveloped Variscan marine basalt and Himalayan alkali- rich porphyry. The Variscan marine basalt generally contains the hydrothermal mineralization, whereas the Himalayan alkali-rich porphyry has a close relationship with gold, iron, lead, zinc, silver. With the Beiya iron gold deposit as the study object, the authors utilized the magnetic anomalies delineated by high resolution magnetic survey in combination with audio magnetotelluric method, (the two methods are mutually complementary), followed the principle of "from known to unknown", and depended on geological data. As a result, deep geological structure and spatial location of the orebody were detected, which can provide a strong guidance for the project layout.