The invention provides a network coverage condition detection method and device and a storage medium. The method comprises the following steps: acquiring coverage levels of a plurality of different first frequency bands corresponding to each grid in a target area; wherein the first frequency band is a frequency band of a first communication system; then, according to the coverage levels of a plurality of different first frequency bands corresponding to the grids, obtaining the coverage levels of the grids; wherein the second frequency band is the frequency band of a second communication system, and then, according to the coverage level of the second frequency band corresponding to each grid in the target area, obtaining the network coverage condition of a second communication system network in the target area. According to the method provided by the embodiment of the invention, accurate prediction of the coverage condition of the second communication system network is realized throughthe equivalent coverage algorithm from the first communication system to the second communication system, and the method provided by the embodiment of the invention does not need a high-precision mapand does not need special drive test, so that the network coverage condition detection cost is effectively reduced.