Geomagnetism, Geoelectricity, Geothermics and Gravity conduct researches from different viewpoints to study Earth’s components and physical operation rules. They are an important part of Geophysics. This course introduces fundamental principles of Geomagnetism, Geoelectricity, Geothermics and Gravity, including their theories, methods, and applications. This course will help students understand the related basic concepts, and provides the basics for subsequent studies of major courses and further researches.