Ag nanocrystal-embedded silicon oxide (SiO2 : Ag) films with varying Ag fractions were prepared on p-Si substrate by magnetron co-sputtering and thermal annealing. Visible electroluminescence (EL) was observed from the structures of ITO/SiO2 : Ag/p-Si. The authors found that Ag nanocrystals in the SiO2 film can not only shift the EL peak evidently but also enhance the EL intensity markedly. The larger the Ag fractions in the EL structures, the longer the peak wavelengths. The electromagnetic interactions of the Ag nanocrystals with the emitters in the film via local surface plasmons are considered responsible for these experimental results.