We propose the global Arnoldi algorithm for MIMO RLCG interconnect model order reductions. This algorithm is an extension of the standard Arnoldi algorithm for systems with multi-inputs and multi-outputs (MIMO). By employing the congruence transformation with the matrix Krylov subspace, the one-sided projection method can be used to construct a reduced-order system. Two kinds of reduced systems using the global Arnoldi algorithm are proposed. The first q-th order of these reduced systems' moments is still preserved. The transfer matrix residual error of the reduced system is also derived analytically. Experimental results demonstrate the feasibility and the effectiveness of the proposed method.