Rockburst is a violent failure in deepburied tunnels. A deepburied tunnel in Chongqing is located in ground consisting of sandstone layers, siltstone layers and mudstone layers, which is subject to rockburst during construction. The mechanical characteristics and dynamic fracture characteristics of the complex surrounding rock combination are studied. The influence of water immersion on the rockburst tendency is studied. The indoor evaluation results on the rockburst tendency are obtained. The paper can provide reference for minimizing the rockburst risks.