In the traditional infrared image non-uniformity correction method, detectors are at room temperature environment. When the environment temperature of detector is changing over a wide range, correction effect of these methods will be worse and not suited. To solve this problem, a non-uniformity correction method based on curved surface fitting is proposed on the basis of original multiple points correction method. Fully considering the environment temperature of detector, original correction curve is increased to correction surface. Subsequent longitudinal comparative experiment and horizontal comparative experiment show that proposed method can greatly reduce the non-uniformity and adapt to the case of changing environment temperature.