Based on the theoretic modal of the erbium-doped fiber dual-ring lasers, the chaotic synchronization by using multivariable unidirectionally coupled scheme is set up. Two different fiber lasers have been investigated and the condition for realizing chaotic synchronization is given. Numerical simulation of the model is established on Simulink and results show that one of the erbium-doped fiber dual-ring lasers as the master laser drives the another slave laser, and they can be completely synchronized even though the decay rate of the two lasers are different and the larger the feedback coefficient is, the faster two lasers achieve synchronization. The feedback coefficient have relationship with decay rate and coupling coefficient. It is also shown that the initial value of the lasers cannot affect the synchronized system, the synchronization is maintained very well. And when the effects of the Gauss noises are considered in the system, they can still reach good synchronization.