A surface plasmonic wave device for biological sensing is demonstrated. It consists of one-dimensional PMMA grating on an aluminum layer. This plasmonic device could increase the fluorescence intensity once the direction of the above dielectric grating and the pumping light could fit to the momentum matching condition. Here we incorporate a spider silk film into such fabricated plasmonic device as an intermediate layer to bridge the inorganic device surface and biological systems of interest. Specifically, a biocompatible spider silk film is casted on the device, followed by further grating fabrication and biomolecular conjugation via enzymatic reactions. Here in the research, antibodies and other proteins are assembled on the fabricated layer of spider silk film specifically with retained activities upon the enhanced fluorescence detection. Unlike other fabrication processes that require material-dependent surface treatments prior to biomolecular conjugation, the additional spider silk film provides an alternative strategy for facile and selective biological assembly in the biosensor. This, we envision, renders an unprecedented advantage for fabricating biosensors with various settings regardless of structural configurations or the building materials of the devices. Overall, the intermediate layer fabricated with spider silk under such grating structures not only demonstrates the strong surface field to enhance the pumping efficiency, but also enables binding of many target biomolecules for sensing and detection.