Abstract Surface plasmons (SPs) have been utilized to enhance the luminescence efficiency of light-emitting materials and devices in the past decade. In this work, the enhanced photoluminescence (PL) from carbon-rich amorphous silicon carbide (a-Si 1− x C x :H) films (with a PL peak at ∼480 nm) has been achieved for the first time via coupling with SPs generated at the Ag/a-Si 1− x C x :H interface. The enhancement factor was found to firstly increase with the Ag nanoparticle size, subsequently reach a maximum value of 3.3 when the average Ag nanoparticle size and the surface area coverage of Ag interlayers were 76 nm and 44% respectively, and eventually decrease as the Ag interlayers became continuous. It was found that such enhancement was mainly due to the SPs scattering. Since the carbon-based films have similar microstructure and PL mechanism to those of the carbon-rich a-Si 1− x C x :H films, coupling with SPs has been proven to be a promising way to enhance the light emission from carbon-based films which can also be utilized for the large-area solid-state lighting applications.