Due to the excessive exploiting of the deep ground water in Xi'an city in the last 50 years, the activities of the ground cracks are recovered. Line 2 of Xi'an Mass Rapid Transit System crosses 12 ground cracks, which include 6 ground cracks with strong activities. On basis of analysis on the causes, features and types of the ground cracks, the paper presents the technical schemes of the structures of the running tunnels crossing the ground cracks recommended in the bidding stage, so that the structures of the running tunnels can be adapted to the deformation of the ground cracks and work well during the 100year design life.