In recent years, scientists of developed countries have paid a great attention on thefruit firmness evaluation by means of non-destructive techniques. The fruit firmness is an important factor for the fruit ripeness and quality, and is also very useful in its planting and storingmanagement. This paper gives a review of studies on evaluating fruit firmness by dynamic techniques. In this paper, the method used for non-destructive detection and the relationship betweenresonant frequencies and firmness are summ...