Abstract: Because the existing conventional wire-line coring drilling tool lacks the water-proof and core-protecting device, the broken core is easily eroded when the core is drilled in a complicated layer such as loose, weak, broken layers and the core is easy to fall off during the lifting process, so that the coring rate and core quality are not up to the design requirements, and even core can not be taken to. In response to the above problems, a bag-type wire-line coring drilling tool was designed. The drill adds a multi-section bundled bag assembly structure to the conventional wire-line coring drilling tool is used in conjunction with the front side spray bit. The bag can isolate the rinsing liquid, which is beneficial to obtain the undisturbed core. By segmenting the bundle, the core can be effectively wrapped to prevent it from falling off during the drilling process. The front side spray bit changes the flow direction of the rinsing liquid and acts as a water barrier and a protector of core. The field application shows that the drilling tool can complete the drilling work in complex layers such as loose, weak and broken layers. The coring rate is over 90%, and the core quality is also obviously improved.