Micro-ring resonators are important devices applicable for optical filtering phenomena. The paper provides the detailed description of general characteristics of serially coupled multiple ring resonator (SMRR). The identical perimeters and coupling coefficients provides the pass band characteristics with flatter top. The paper includes the concept of Masons gain formula and its application in order to analyze the transfer characteristics of single and multiple ring resonator structures. The graphical approach provides the fast derivation of transfer function of SMRR. The results are properly verified with the MATLAB.