The invention provides an electro-hydraulic mix-drive mining cable shovel and an excavating mechanism thereof. The excavating mechanism comprises a bucket rod, a bucket, a hydraulic drive mechanism and a lifting mechanism. The hydraulic drive mechanism is rotatably connected between the bucket rod and the bucket and used for driving the bucket and the bucket rod to relatively rotate. The lifting mechanism is rotatably connected to the upper end of the bucket. The excavating mechanism is connected with a cable shovel body through the bucket rod and the lifting mechanism. The bucket rod pushes under driving of a drive motor, and the lifting mechanism lifts also under driving of the drive motor. The bucket rod is connected with the upper end of the bucket through a rotating joint. The hydraulic mechanism is added to the lower portion of the bucket rod to drive the bucket to rotate. The hydraulic drive mechanism comprises a hydraulic cylinder, a middle link and a pull rod and drives the bucket to rotate relative to the bucket rod. The excavating mechanism is more flexible and capable of completing complex excavating actions, loading bucket factor is increased, excavating resistance is reduced, and excavating efficiency is improved.