The invention provides a method and a system for realizing accurate positioning by enabling a locomotive to pass through a station yard detection area and applies to the technical field of railway yard management. The method comprises the following steps: obtaining a first sensing signal output by a first sensor mounted in a set position of the station yard detection area when the locomotive passes through the detection area; obtaining a second sensing signal output by a second sensor mounted in a set position of the station yard detection area when the locomotive passes through the detection area; positioning the running state of the locomotive in a station yard at least according to whether the first sensing signal and the second sensing signal can be obtained, and outputting a positioning result. Starting from the site environment of the locomotive, one simple and effective locomotive positioning method is provided, and the site management efficiency of the station yard is increased.