Abstract:The paper uses tank simulation experiments to obtain electrical potential anomaly of single model, lateral and vertical array models. The experiment uses stainless steel pipe for simulating metal pipe, thin copper rod for power-supplied electrical pole, high-resistant isolated plate for oil horizon, red copper for water layer and network electrical potential recorder with 128 channels for recording. It can provide foundation for using well-to-ground electrical survey to study oil/gas reservoir or water-bearing layer through studying anomaly regu- larity of electrical potential isopleths on the ground when high-resistant or low-resistant anomalous bodies exit in power-supplied steel-cased well. The simulated results showed that direct-current charge method, which is one of well-to-ground working mode that measures distribution of electrical field on the ground (or on the water surface) when supplying direct current to the oil well,can effectively eliminate the influence of non-uniform conductivity above on objective oil/gas reservoir,especially,the well-to-ground electrical survey can trap the distributed scope of different reservoirs when coexisting several sets of oil-water layers and certain distance exists among these layers. So, this method can play an important role in oilfield development and monitoring in waterflood stage as well as looking for the residual oil/gas distribution.