Abstract: Global output regulation problems for nonlinear control systems are discussed. First, a state feedback diffeomorphic coordination transformation is introduced to transform the nonlinear system into the system which consists of a linear system and a nonlinear exosystem. Then solvability of output regulation is defined to discuss the global output regulation problems of this special control systems. The result is an extension to that ofthe linear systems. Finally, it is shown that if the exo-system is the solvable and the condition of global exact feedback linearization is satisfied then the global output regulate problem for nonlinear systems is solvable. If only local feedback coordination transformation exits ,we can obtain the local results.