The Agrobacterium-mediated transformation system is more and more attractive to scientists of microbiology, molecular biology and crop genetics and breeding due to its unique advantages, which promote its development rapidly in the past decade. Great success has been achieved in the Agrobacterium-mediated genetic transformation system in maize (Zea mays L.), an important food-supply crop. This article highlights the advances of Agrobacterium-mediated transformation system of maize and the major factors of the transformation process. Then, comments on the problems remained and the prospects of this transformation system are made.