Abstract: Based on serious interference and target fluctuation which HF radar is faced with, it is proposed that multi-frequency detection technique from range radar is applied to HF radar to overcome the restrict the above problem mentioned. Moreover, this paper puts forward an algorithm of multi-frequency information fusion based on non-coherent integration. The algorithm makes non-coherent integration in speed domain, obtaining high signal-to-noise ratio to improve the ability of target detection in HF Radar. Through both simulated and experimental data, the proposed algorithm can improve the signal-to-noise ratio close to the theoretical value, which indicates that this algorithm is effective.