Single-polarization single-mode (SPSM) fiber can efficiently eliminate polarization mode coupling, polarization mode dispersion, and polarization-dependent loss. Up to now, most single-polarization fibers have been designed based on form birefringence, which would result in a non-Gaussian field distribution and a small effective mode field area. In this paper, a novel structure of SPSM photonic crystal fibers based on the resonant coupling phenomena is proposed and analyzed by using a full-vector finite-element method with a second-order transparent boundary condition. From the numerical results it is confirmed that this fiber has a near-Gaussian mode field within the wavelength range from 1.46 to $2.2\mathrm{\mu m}$ , where only one polarized mode exists effectively, and the mode field area is about $79{\mathrm{\mu m}}^2$ at the wavelength of $1.55\mathrm{\mu m}$ , matching that of the conventional single-mode fiber.