This paper describes the experimental investigation of stimulated Raman scattering and stimulated four photon mixing obtained from an Er doped silica fiber. Six orders of stimulated Stokes scattering in the range of 552.1～622.8 nm and the Stokes (λ=542.9 nm) and anti Stokes (λ=537 nm) of stimulated four photon mixing have been obtained from a 10 m Er doped single mode silica fiber, which was pumped by a frequency doubled Q-switched Nd:YAP laser (λ=539.7 nm) with a pulse duration of 50 ns. Its output energy is 0.1 J.