AFT is one of the major pollutants in food agricultural products. The key to preventing the AFT poisoning of livestock is to avoid the AFT feed being eaten. Therefore, it is necessary to study the contamination situation of feed caused by AFT, which is highly useful for the aquaculture development, and the rapid screening of AFT is an important step in this process. Based on the fluorescence characteristics and mechanism of AFT, this paper uses the UV LED as the excitation source and adopts the color-sensitive sensor to carry out fluorescence signal acquisition and photoelectric conversion, controlled by MCU, to design the screening device for AFTB1 contaminated feed. This screening device is produced as a rod, for it is easy to be inserted in the feed pile. Besides, it is easy to carry and operate, durable and reliable and has low cost, which can be used to make qualitative screening for the AFT quickly.