In view of the complex dynamic changes of tire pressure during the inflation process of off-road vehicle tires, a real-time prediction method of tire pressure during the inflation process was proposed. The method mainly comprise a data acquisition and preprocessing module, a pre-calibration tire air resistance module and a tire pressure estimation module, wherein a tire air resistance value is estimate according to a tire pressure value of a pressure measuring working condition; and on that basis, the tire pressure estimation module circularly estimates the tire pressure by using a pneumatic principle. Through the verification of the tire central inflation and deflation system platform, the results show that the root mean square error of the algorithm is not more than 0.084 3 MPa, which greatly improves the accuracy of tire pressure prediction.