The invention discloses a large hydraulic extreme weather simulator which consists of three functional areas, namely a high and low temperature humidity alternating, sunlight and wind speed simulation area, a salt mist, rainstorm and etchant gas simulation area and a temperature impact simulation area. The large hydraulic extreme weather simulator is characterized in that a test simulator can be used for simulating extreme weather parameters such as high and low temperature, humidity, rainstorm, sunlight and wind speed, environmental conditions such as aging, corrosion and pressure water as well as a coupling action of the extreme weather parameters and the environmental conditions. According to the invention, parameter simulation of single mode such as high temperature, low temperature, humidity circulation, cold wave attack, long-duration heat and drought, temperature impact, salt mist, acid gas corrosion and pressure water environment and coupling of the single mode, a load and a pressure water environment are realized through the three functional areas; key test parameters are provided for research of hydraulic structure basic materials and members for safely coping with the extreme weather, and the large hydraulic extreme weather simulator has the characteristics of capability of simulating an actual service environment, wide applicability, strong operability and the like.