Loess soils are widely distributed worldwide and typical in northwest China, and excessive agricultural irrigation has caused landslides in the area, specifically in the Heifangtai loess region in Lanzhou, Gansu, China. Geophysical exploration is an essential method in landslide engineering geological surveys, and geological surveying, drilling, geophysical prospecting, monitoring, and other methods are used for performing engineering geological evaluation and obtaining comprehensive basic data for landslide protection design and construction. The theoretical feasibility of using geophysical methods in loess landslide detection is essential. On the basis of the shallow geological structure of the Heifangtai landslide region in Lanzhou, Gansu, China, a typical geoelectric model of the magnetotelluric method was established, and the loess landslide area was modeled through a two-dimensional finite element method, forward numerical simulation, and engineering geological analysis. The distribution characteristics of the magnetotelluric field were determined. This is a typical application of the geological process analysis method in geophysical exploration. This study provides the typical stratigraphic structure and electrical characteristics of different groundwater distributions in Heifangtai, Gansu, China, verifies the accuracy of forward modeling and calculation results, and provides a detailed theoretical basis for landslide detection through magnetotelluric methods. Through the numerical simulation of the forward modeling of the Heifangtai landslide region in Lanzhou, Gansu, China, this study can provide a detailed geophysical basis for landslide investigation, corroborate results of geological investigation and landslide design, and facilitate the sustainable development of agriculture in Heifangtai.