The surface wave modes on right-handed helically grooved metal wire waveguide and left-handed one were studied and compared. It was found that for the helically grooved waveguide, the normal degenerate HE1 SSPP (spoof surface plasmon polaritons) mode decompose into two opposite circularly polarized modes, i.e., HE − 1 and HE + 1 SSPP modes due to the chirality of helical grooves. The divarication between dispersion curves of HE + 1 and HE − 1 modes can generate a circular-polarization band. Moreover, a positive or negative superchiral field can be obtained for the right-handed grooved and left-handed grooved wire respectively due to the near field enhancement effect.