Clean and uniformly distributed silver nanoparticles (AgNPs) are deposited on glass substrates using a vacuum evaporation process. The localized surface plasmon resonance (LSPR) of these AgNPs is successfully tuned from 420 to 780 nm by changing the evaporation time from 20 to 180 s. Further, it is found that the LSPR can be shifted to shorter wavelength in the range of 410 to 478 nm by annealing in flowing nitrogen at 200 °C for 10 min. The blueshift is correlated with the changes in microscopic features of the AgNPs, as revealed by SEM and AFM images. Rhodamine 6G (R6G) was chosen as the probe molecule to explore its coupling with AgNPs before and after annealing. Analysis of extinction spectra suggests that strong coupling takes place when the LSPR is close to the absorption of R6G.