In this paper, a surface-enhanced Raman scattering optical fluid chip based on long-range plasma waveguide is designed. The dielectric waveguide is used to excite plasma waveguide. The coupling signal transmit through the plasma waveguide and dielectric waveguide. It may reduce the transmission loss and increase transmission distance. The excitation light of 632.8 nm is used. The gold (Au) is as a plasma waveguide core layer and PTFE is as dielectric optical waveguide core layer. The simulation results show that the dielectric optical waveguide width of 4 μm, thickness of 0.2 μm, plasma waveguide width of 4.5 μm, thickness of 13 nm, the spacing D between two waveguide of 3.1 μm, coupling effect is best. The field intensity is about 1.8024×108 and the transmission distance is about 0.3 mm which is twice of used alone the plasma waveguide transmission distance. This study provides a theoretical basis for long - range detection of surface-enhanced Raman microfluidic chip.