In order to achieve accurate positioning of diesel engine abnormal noise, an NI data acquisition system was used to collect the noise signal of diesel engine and the noise signal was filtered with an A weight coefficient filter to obtain a noise signal similar to that received by the human ear. The signal had less low frequency interference and the proportion of meaningful signals increased from 12.62% to 29.79%. By using the Stochastic Region Contraction Phase Transform Weighed (SRC-PHAT) method, the initial search space region was established and the steered response power (SRP) at the randomlyselected points in the region was calculated. A new search space area was established with the area with a large SRP value so that the iterative operations were conducted until the target area accuracy of search area reached the approximate position of abnormal noise source. The experimental results show that this method has good accuracy for diesel engine abnormal noise positioning and provides the reference for the positioning of engine abnormal noise.