The semiconductor laser beam and computer vision technology were used to monitor the surface damage and inner decay of apples (c.v.gala). In the experiments, the damage was produced by falling of a spherical steel ball (diameter: 16mm, weight: 96g) on the apples from a height of 20cm, to simulate the damage caused during the picking and transportation. In order to simulate the inner decay, 15μL suspensions at 105/mL conidia of Penicillium expansum was injected into the inner of the apples by a micro-injection. The laser scattering image analysis indicates that the number of the pixels of the images (S3) reached the maximum (3964) after 36hours after damaged, and had significant differences with the control group during 84 hours after damaged (P≤0.05).After injecting the suspensions, the number of the pixels of S3 reached the maximum (3682) on the 4th day, and showed significant differences with the control group on the 7th day (P≤0.05). This trial laid a theoretical basis for applying low power laser beam to monitor the surface damage and inner decay of apples.