Abstract-The electromagnetic scattering by a homogeneous gyrotropic bianisotropic cylinder of arbitrary cross section is analyzed in this paper using the generalized multipole technique (GMT) where only the longitudinal fictitious electric and magnetic currents are involved. The general scattering solution is formulated and numerical results of near fields and bistatic radar cross sections are presented for four specific examples, namely, a chiral circular cylinder, a chiral square cylinder, a gyrotropic bianisotropic circular cylinder, and a gyrotropic bianisotropic "lens" cylinder. Results obtained using the GMT for the chiral and the gyrotropic bianisotropic circular cylinders are in excellent agreement with those obtained from the eigen-function expansion. Results of the GMT for the chiral square cylinder are in excellent agreement with those obtained from the method of moments (MoM) solution.