In order to study the relationship between the wheat scab situation, rate of diseased grains and DON content, wheat samples contracted with wheat scab in different degrees were selected to determine DON content in grains by HPLC. The results showed that the DON content in wheat grains increased along with the increasing of field disease severity or the rate of diseased grains, which showed highly significant correlation. It was of certain practicality to calculate the DON content on the basis of the rate of diseased grains. But when it came to different wheat varieties and the disease severity, the theoretical value error was bigger.