A propagation channel estimation method is provided. In-phase and quadrature components of a propagation channel estimation value in each pilot subcarrier are separated into amplitude and phase components. A propagation channel of a data subcarrier portion existing between pilot subcarriers is estimated by phase/amplitude separation linear interpolating in each separated amplitude and phase component. A reference parameter is produced by linear interpolating a portion between pilot subcarriers on a complex plane. When quadrants on the complex plane of the interpolated phase component estimation value and the reference parameter are different, a phase connecting process to cancel a discontinuity of the phases is executed to the phase component estimation value interpolated by the phase/amplitude separation linear interpolation. When the quadrants are not different or after the phase connecting process, a complex propagation channel estimation value of the data subcarrier portion is calculated from the phase and amplitude components of the propagation channel estimation value.