The objectives of this research were to study the effect of moisture content and temperature of corn stored in where-houses and out-doors for production and determination of Aflatoxin B1 in Syria. 200 tons of corn crops was used for our experiment, and was divided 100 tons each for storage out-doors and in-doors respectively according to General Company of Feed Stuff in Syria. Samples had been taken for 12 months by using stratified random sampling method.