In this paper, a new concept of few-mode waveguide is proposed. Based on the plane-wave expansion method and the finite-difference time-domain method, this concept is demonstrated in the Kagome lattice line defect structure. By changing the parameters of defective dielectric columns (radius, location) and inserting new defective columns between original medium columns, a two-mode Kagome lattice waveguide structure with a bandwidth of 0.08888ωa/2πc is obtained. This few-mode waveguide structure provides a new idea for the design of photonic crystal planar waveguide and will have important application value in photonic integration and other fields.