Based on ZigBee and GPRS, a system was designed to acquire farmland images and transfer the images wirelessly. The system consisted of MESH-type ZigBee network for image acquisition and a remote server which could communicate with the ZigBee network coordinator via GPRS network. The image acquisition based on the V4L technology was introduced first, and the process of JPEG compression and decompression was described, the method of reducing the computational complexity of image compression by the improved discrete cosine transform (DCT) was studied, then how to improve reliability in the data transmission by partitioning and checking image data was discussed. At last, the system was tested in the given field and it proved that the successful rate of farmland image acquisition was 76%. Furthermore, the difference between the theoretical and practical transmission time was analyzed.