Abstract: An efficient iterative method is presented for fast analysis of cylindrically conformal microstrip structure. Based on the transmission line modeling (TLM) method and the fast mode transform (FMT) theory, this method accelerates the process of the calculation by introducing the concept of the transverse electromagnetic waves instead of the transverse fields considered in the traditional algorithm. In the cylindrically stratified media, the transverse electromagnetic waves are represented by mixed modal basis functions. Ultimately, the material form of the modal admittance and the spectral reflection operator are deduced. The surface electric field and electric current of the cylindrically conformal microstrip antenna fed by means of a microstripline are calculated via wave concept iterative process. On this basis, the input impedance of the antenna can also be obtained. The results gained by utilizing WCIP are compared with those from published references to demonstrate the accuracy or efficiency of the method.