To solve the problem that the Hydroxyl-Terminated Polybutadiene(HTPB) propellant aging characteristics at different storage stages cannot be described by commonly used aging models accurately, the segmented aging model was proposed. The high temperature accelerated life test of the HTPB propellant was carried out, and the aging mechanism of HTPB propellant was analyzed in three stages by using the maximum elongation as the characteristic parameter. According to the correlation analysis results of different aging stages, the segmented aging model was established. The time conversion relationship between high temperature (60 ℃) accelerated aging and room temperature (25 ℃) effective storage was obtained by using the time-temperature equivalence principle, and the storage life of HTPB propellant at room temperature (25 ℃) is predicted for 11.60 years by combing with the segmented aging model. The correlation coefficient R of the segmented aging model is more than 0.95, and the standard deviation R_std is less than 0.015.