The surface plasmon resonance (SPR) based optical fiber sensor is a novel sensor, which takes optical fiber core as a substrate to excite SPR effect. This paper demonstrates a virtual simulation platform for design of optical fiber SPR devices on the basis of LabVIEW, and makes theoretical calculations according to material parameters and component architecture, which can change the size and material parameters in situ to understand the impact on SPR effect, and furthermore to find the optimum parameters. Finally, based on side-polished PMMA plastic optical fiber, the simulation shows that 40nm silver-plated thin film on the grinding surface results in a better performance of optic fiber SPR sensor. In terms of the optimum parameters of the sensor, the relationship between the resonance wavelength and the refractive index of sampling solution can be obtained.