The presence of deoxynivalenol (DON) in cereal-based baby food, a primary source of the first solid food for infants, was studied in order to develop a method to detect its presence at low concentrations. DON, produced primarily by Fusarium graminearum, is commonly isolated from grains and feed around the world and affects both animal and human health, producing diarrhea, vomiting, gastrointestinal inflammation, and immunomodulation. An aqueous extract of infant cereal was cleaned by means of an immunoaffinity chromatography column. After the eluate was evaporated and redissolved, DON was determined by high-pressure liquid chromatography-UV. The level of quantification for DON was 10 ppb for three types of infant cereal (mixed, barley, and oatmeal); the level of detection was 5 ppb. The protocol we have developed can measure DON between 10 to 500 ppb. An advisory level of 1 ppm for wheat products has been established by the U.S. Food and Drug Administration; however, the European Communities (EC) regulations have been set at 200 ppb for cereal-based foods for infants. Only 1 of 52 samples of barley-, mixed-, or oat-based infant cereal purchased in 2008 and 2009 in the United States exceeded the European standard.