Abstract: New progress and application of nonlinear acoustics in recent years were reviewed,and four aspects were emphasized:(1) nonlinear parameter B/A determination: besides conventional methods,the new methods for the determination were introduced in belief,also the measurements of the solid nonlinear coefficient.(2) nondestructive evaluation: this is the most potential application of nonlinear acoustics,because the fatigue of material is closely related to high nonlinear acoustic behaviors.(3) buried target detection: this is based on the soil/mine coupled system,and similar to the nonlinear acoustic characteristics of the porous/NME material.(4) medical harmonic imaging: three types of imaging(UCAI,THI and EHI) and their mechanism were described.