In order to solve the ambiguous acquiring problem for Binary Offset Carrier (BOC) modulated signals caused by multiple peaks of its autocorrelation function,we put forward a new acquisition algorithm based on combined correlation functions for BOC(n,n) signals through analyzing the autocorrelation function of the BOC modulated signal and the existing acquisition algorithms,and by use of the traditional acquisition algorithm of parallel code phase search acquisition.The algorithm is realized by adopting the autocorrelation of BOC(n,n) signal and cross-correlation of BOC(n,n) with Pseudo Random Noise(PRN) code,and through the operations of shifting ±Tc/2,summing,modulus and squaring.The theoretic analysis and simulation results show that:The proposed algorithm can remove the related side-peak,significantly improve the main-peak value and keep the autocorrelation peak width,while having an ideal acquisition performance,less computation cost,and is easy to implement.