This paper studies the synchronization problem of fractional-order neural network with delay, gives the analytic formula of synchronized controller by using Mittag-Leffler function and linear feedback control, receives the sufficient condition for delay neural network synchronization on Caputo derivative, i.e., the condition for system synchronization is easy to be proved and be implemented as well as only depends on the structure of the system, and finally verifies the validity of the theory by numerical simulation.