Acoustic logging while drilling (LWD) is an important method to obtain formation information accurately, but the direct wave propagating along drill collar seriously interferes with the measurement of formation wave. In order to eliminate the influence of drill collar direct wave on logging data, a new method of eliminating drill collar direct wave by using single sound source opposite phase excitation is proposed. According to the method, an emission sound source is simulated through an adaptive filtering active noise control technology, so that the aim of mutual elimination of the same frequency and opposite phases when two drill collar direct waves excited by a single sound source and a virtual sound source reach the same receiver is realized, the influence of the drill collar direct wave on formation wave signals is eliminated from the source, and the logging risk caused by reducing the mechanical strength of the drill collar due to physical processing of the drill collar is avoided. Through the analysis of the principle model of delayed inverse excitation by a single sound source, the simulation calculation of the principle model and the processing of actual logging data by developing software based on adaptive filtering active noise control technology, it is verified that the new method has obvious effect on eliminating drill collar direct wave in acoustic logging while drilling.