As the main objects, imagoes have been researched in quarantine pest recognition in these days. However, pests in their
larval stage are latent, and the larvae spread abroad much easily with the circulation of agricultural and forest products. It
is presented in this paper that, as the new research objects, larvae are recognized by means of machine vision, image
processing and pattern recognition. More visional information is reserved and the recognition rate is improved as color
image segmentation is applied to images of larvae. Along with the characteristics of affine invariance, perspective
invariance and brightness invariance, scale invariant feature transform (SIFT) is adopted for the feature extraction. The
neural network algorithm is utilized for pattern recognition, and the automatic identification of larvae images is
successfully achieved with satisfactory results.