Based on the phobophototaxis of rice plant hoppers and the method of capturing insects applied by crop protection experts, a kind of automatic acquisition system for insects images in field environment was developed. The system was consisted of a computer, an insect capture platform, an image acquisition device and controlling system. Firstly, a fluorescent lamp was utilized to attract wild insects on the curtain screen installed on the capture platform. Later, with the 2-D movement of the capture platform and the white curtain, the image acquisition device controlled by the computer and microprocessor took photos of insects on the curtain screen at regular intervals. Hence the images of insects in a natural status were obtained. Experimental results showed that the system could be used to obtain clear and complete images of insects in a natural status. The study provided facilities for the automatic identification for rice plant hoppers and the prediction of the density of the rice plant hoppers in fields. 