Abstract: A novel algorithm for feature extraction of the precession angle and real length of the ballistic target using multi-aspect observed High Range Resolution Profile (HRRP) sequences is proposed. Taking the cone-shaped ballistic target into consideration, this paper analyzes the HRRP length when the target is precessing and indicates that the sequence of HRRP lengths can be approximate to a sinusoid function. Then, the model of multi-aspect observation is introduced and a novel algorithm, which is based on the multi-aspect observed HRRP sequences, is proposed to estimate the precession angle and real target length jointly. Afterwards, the effect of the radars distribution on the estimated errors is discussed. Finally, the simulation results are given for validating the proposed algorithms.