Abstract: In recent years, magnetic exploration has achieved good results in finding hidden pegmatite veins and deep prospecting prediction, but the role of ground high-precision magnetic survey in the exploration of pegmatite spodumene deposits is often overlooked. In order to study the applicability of ground high-precision magnetic survey in finding hidden ore bodies, this paper takes the Jiajika mining area as an example and selects representative rock samples in the mining area for magnetic parameter measurement. The study shows that the magnetism of rocks and ores in the Jiajika mining area is weak overall, but there are high magnetic susceptibility and residual magnetization intensity in local areas. The 1: 50, 000 geomagnetic anomaly characteristics show that there are a series of medium-strong positive or negative anomalies in the Jiajika dome area, which are related to pegmatite veins. The 1: 5000 magnetic survey profile data further confirms that these anomalies are mainly caused by deep underground geological factors. Comprehensive analysis shows that the geomagnetic field characteristics of the Jiajika mining area are significantly different from those outside the dome area. Ground high-precision magnetic survey plays an important role in the exploration of pegmatite spodumene deposits. Its application potential cannot be ignored because spodumene deposits are non-magnetic. It also has certain reference significance for the prospecting of similar deposits.