The efficient coupling of fiber and planar optical waveguide is an important link in the interconnection design of optical waveguide devices. The commonly used inverted tapered waveguides have solved the problem of mode mismatch between fibers and waveguide chips. However, the coupling of high refractive index difference waveguides and fibers usually requires a small tip size (<180 nm), the processing is complicated and the waveguide is easy to collapse. A broad-band (visible and near infrared bands) fiber-waveguide horizontal coupler is designed. By introducing the polymer SU-8 tapered structure, the linewidth of the three-port branch waveguide is improved, and an effective bandwidth of 1dB over 300 nm in 850 nm wave band is achieved.