A novel solution-processable erbium-ytterbium co-doped complex was successfully synthesized and used to fabricate a waveguide amplifier. The absorption and photoluminescence spectra of the complex were observed. The full width at half maximum (FWHM) was about 80 nm. An embedded waveguide structure was fabricated using the complex as the core layer and SU-8 material as the cladding layers. With an input signal power of 0.2 mW and pump power of 133.6 mW, an optical gain of 4.14 dB at a wavelength of 1550 nm was obtained in a 29 mm-long waveguide.