Disclosed is an exploration method and system for pegmatite veins. The exploration method includes: three grounding electrodes are arranged at each observation point in a target area where pegmatite veins are located, and collecting electric field differences between two groups of grounding electrodes; drawing a multi-channel map, based on positions of the grounding electrodes, according to the electric field differences; obtaining resistivity variation characteristics of pegmatite veins according to the transverse variation of multi-channel map, and determining locations and lithologic characteristics of pegmatite veins according to the resistivity variation characteristics. Through functional modules with different functions, an exploration system is formed to realize the exploration method mentioned in the application.