Hydraulic releasing mechanism, hydraulic releasing packer and pump sealing integrated production string

The utility model relates to a hydraulic releasing mechanism. The hydraulic releasing mechanism comprises an upper joint and a releasing internal pipe which is fixedly connected to the lower end of the upper joint; a releasing external pipe is slidingly sleeved on the releasing internal pipe; the releasing internal pipe is connected with the releasing external pipe through locking blocks which are radially embedded into pipe walls of the pipes from the external pipe surface of the releasing external pipe; a locking block pressing sleeve is slidingly sleeved on the releasing external pipe, the locking block pressing sleeve is provided with a step sleeve which consists of a locking segment slidingly matched with the external pipe surface of the releasing external pipe and an expanded unlocking segment, the locking blocks are pressed at the locking segment of the locking position, and when the locking block sleeve upwards moves to the unlocking position, the locking segment is positioned above the locking blocks