The operation reliability of diesel engine and entire power system was seriously affected by the high frequency vibration of diesel engine turbocharger. The identification and analysis of main vibration sources for the turbocharger could effectively guide the vibration control and optimize the vibration response of body. For the turbocharger vibration response characteristics of high frequency, wide frequency band and time-varying unsteady state, the continuous wavelet transform method was used to carry out signal identification and analysis of dynamic vibration source under transient excitation because it had the advantages of time-frequency characteristics such as the multi-scale calculation and analysis frequency and the precise determination of occurrence time in signal processing. Combining the structural characteristics and working principle of turbocharger, the main vibration sources of turbocharger were identified and analyzed under the transient condition. The time-frequency characteristics of excitation were obtained including aerodynamic load and rotor mass imbalance. By analyzing the vibration response spectrum characteristic information of turbocharger under the steady-state condition of 50 513 r/min, the main vibration source identification results were analyzed and verified. The research results showed that the continuous wavelet transform method can intuitively and accurately identify the time-frequency characteristics of turbocharger vibration source. Under transient and steady conditions, the turbocharger vibration is mainly affected by the aerodynamic load excitation, which is characterized as the air impact vibration at the blade passing frequency and the structural vibration with high frequency and wide frequency band. Under steady-state condition, the turbocharger is significantly affected by the rotor mass imbalance excitation, which is characterized as the vibration response peak phenomenon at the rotation frequency and multiplication frequency.