A new iterative T-matrix algorithm combined with iterative scattering process (ISP) has proposed for dealing with the scattering characteristics of cylindrical objects. The relationship between incident and transition filed can evolve from the cylindrical harmonics of one cylinder. With the iterative scattered field among cylinders each time considered as the incident field of iterative process next time, the total iterative scattering matrix can be reached. After analyzing the curves for iterative each time, the verification that the process of iterative among the cylinder array is equivalent to the coupling process among cylinders could come out. To test the veracity of the iterative T-matrix theory, the scattered field of four cylinders with arbitrary radius and location has been calculated with both iterative T-matrix algorithm and the method of moments (MoM). The results compared are shown that the iterative T-matrix algorithm and MoM agree well.