Abstract: Aiming at the production process of animal food, the design problems of the key marking technique in traceability system of animal food were discussed. The test results of the reader and electronic tag showed that the communication distance and signal intensity gradually increased with the multiple decrease of data transfer rate. When data transfer rate was 60 kbps or 10 kbps, better communication effect could be achieved. And the signal could be accurately identified in the range of 50 m. The parameters should be chosen in the actual application according to the reading quantity of tags, the communication distance and disturbance conditions.