The present disclosure discloses an electroluminescent display screen and brightness uniformity compensation method and system thereof, wherein the method comprises: performing test modeling based on a correspondence between an aging rule of an electroluminescent diode in the display screen and an aging rule of a thin film transistor (TFT) in the display screen to acquire a brightness uniformity compensation model; acquiring a first compensation parameter and a second compensation parameter required for compensating the TFT, and acquiring a current brightness ratio of the electroluminescent diode through invoking the brightness uniformity compensation model based on the compensation parameters; performing brightness uniformity compensation on the display screen based on the acquired current brightness ratio of the electroluminescent diode.