During the Wenchuan M_S8.0 earthquake on May 12, 2008 and the Lushan M_S7.0 earthquake on April 20, 2013, surface rupture phenomena did not occur on the Yanjing-Wulong fault in the southern segment of the Longmenshan central fault zone. Moreover, shallow geophysical data for the Yanjing-Wulong fault are extremely scarce. The seismic hazard and the capacity for potential earthquakes were evaluated in the southern section of the Longmenshan fault zone to a certain extent. However, the major counties (towns) crossed by the Yanjing-Wulong fault are mostly located in valleys with widths less than 300 m. As a result, such detection areas are subject to inconvenient traffic conditions and narrow working spaces. Therefore, detection through shallow seismic reflection must be applied with small trail spacing, small displacement distance, reception of multiple short arrangements, multiple coverage observations of common reflection points, and data processing. In the present study, shallow seismic reflection is combined with high-density resistivity tomography, trench excavation, and drilling to reveal the size, spatial distribution, and near-surface structure of the NE-trending Yanjing-Wulong fault in the area of Dongfeng village, Wulong, Baoxing County. These detection results not only provide reliable seismological evidence for determining the near-surface activity of the Yanjing-Wulong fault but also offer scientific fundamental data for selecting sites for post-disaster reconstruction, earthquake risk assessment, and planning of earthquake resistance and hazardous prevention in the Baoxing County.