The invention discloses an obtaining method for ground lightning and operation impulse altitude correction values of 500kV electric equipment at the altitude of 2km-4km and relates to the field of high-altitude ultrahigh-voltage transmission and transformation projects. The technical key points comprise the step 1 of calculating out a ground lightning impulse insulation level correction coefficient of a soft bus in some area at the altitude between 2000m and 4000m according to a formula Ka=(1.633-1.278)/(4000-2000)*(H-2000)+1.278, the step 2 of inquiring a ground lightning impulse insulation level value of the soft bus in an area at the 0 altitude, and the step 3 of using the correction coefficient Ka to multiply by the ground lightning impulse insulation level value, inquired from the step 2, of the soft bus in the area at the 0 altitude to obtain a ground lightning impulse insulation level altitude correction value of the soft bus at the H altitude. In addition, the H is the altitude, and the value range of the H is 2000m-4000m.