Aiming at the difficulty of detecting transient power quality disturbances in noisy environments,this paper proposes a detection method based on the combination of wavelet modulus maximum and hierarchical adaptive threshold function. Firstly,in order to effectively reduce the noise of the disturbance signal, in other words, to ensure the smoothness of the signal after noise reduction and retain the mutation point information, adaptively adjusted HATF is adopted. The function is derivable at the threshold and in the wavelet domain, avoiding the defect that traditional or improved threshold functions can not reduce noise or reduce noise excessively. Secondly,based on the WMM method,the transient power quality disturbance after noise reduction is located by the position of the modulus maximum point in the detail coefficient. Based on noisy single and composite disturbance signals, simulation and comparative analysis show that HATF has obvious advantages in noise reduction and WMM+HATF has good versatility and high positioning accuracy.