The invention belongs to the technical field of rock mass mining fracture permeability determination, and discloses a borehole single loop pressurized-water control system based on overlying strata diversion fissure zone detection. The borehole single loop pressurized-water control system comprises a plugging test system, a propelling system and a supply control system. The plugging test system comprises a plugging device, a communicating pipe and a transverter, and a water injecting cavity is formed by the plugging device and a drill hole. The transverter is located on the tail portions of afront portion plugging device and a middle portion plugging device, and is internally provided with an inner ring, a spring, a cross wire sleeve, a water storage tank and a water diversion hole, the inner ring is provided with a water passing hole and communicates with the water storage tank, a externally-connected water source is transported to the water-injection cavity through the water diversion hole, and the permeability of the borehole fracture is detected. The borehole single loop pressurized-water control system based on the overlying strata diversion fissure zone detection can use thesame water source to realize the plugging and observation process under the respective pressure, pipes in a borehole is reduced to one, the problem of the drill pipe winding is avoided, the stabilityof the observation process is improved, the observation water pressure can be adjusted according to the need, the measurement process of propelling multiple stages at one time can be realized at thesame time, and the observation efficiency is improved.