The invention discloses a self-adaptive hydraulic cyclone desilting device for relatively large turbidity change, and is characterized in that a mixed flocculation zone is arranged at the center of apool body, a precipitation separation zone is arranged around the mixed flocculation zone, an annular partition wall is arranged between the mixed flocculation zone and the precipitation separation zone, and the mixed flocculation zone communicates with the lower side of the precipitation separation zone; the bottom of the pool body is a sludge concentration zone; an adjustable guide cylinder is arranged in the mixed flocculation zone; an annular distribution tube is arranged around the adjustable guide cylinder; the annular distribution tube is connected with a water inlet pipe, a plurality of nozzles are arranged on the annular distribution tube, and the plurality of nozzles are arranged in the same direction in the circumferential direction; a water collecting tank is arranged above theprecipitation separation zone; a mud scraper is arranged in the sludge concentration zone. The self-adaptive hydraulic cyclone desilting device has the advantages that a pool-shaped structure is simple, the sludge discharge is relatively reliable, when in response to original water with different properties, the device has good adaptability to the original water with high turbidity and relativelylarge turbidity change by changing of the installation height of the guide cylinder and automatic adjustment of a mud scraping plate of the mud scraper.