Refractive index resolution is an important indicator for a wavelength interrogation surface plasmon resonance sensor. which can be affected by signal-to-noise ratio. This paper investigates the impact of spectral signal-to-noise ratio on a surface plasmon resonance sensor. The effects of different spectral powers and noises are compared and verified through simulation and experiments. https://www.spidertattooz.com/SNS-Dipping-Powder-Trendy-Grey-1-oz-NOS21-p35616/