The output of conventional Teager energy operator (TEO) is approximately equal to the square product of the instantaneous amplitude and the instantaneous frequency ( A 2 Ω 2 ). The original TEO can effectively enhance the transient shock components and suppress the non-impacting elements, and it also changes the frequency distribution of the original shock. In this paper, a complete Teager energy operator is proposed, and its expression is more exact than original method. By keeping the positive and negative distribution of the shock signal x ( t ), the fundamental frequency energy of the impulses can be effectively enhanced. The incipient fault characteristics of large-scale rotating machinery are typically micro shock pulse, extremely weak and mixed with heavy noise. Preprocessing the fault signal and enhancing the micro shock component are essential means to extract the early fault features. In the experiment part, the applicability of the proposed method is verified by the simulated micro impact signal, the common bearing fault data-sets and the practical measured data of the test bench.