Surface plasmon polarization(SPP)waveguides consisting of dielectric claddings and metal thin films have been shown to transmit optical signals beyond the diffraction limit.It is appealing for nanoscale integrated optical systems.We have designed and fabricated a compact and nanometric SPP thermo-optic switch by spin-coating,ultra-violet lithography and vacuum evaporation technology.Low loss polymer materials are used as cladding layers and high quality gold thin film is served as core layer of SPP waveguides.After fabrication process,the performance of the devices is characterized using a 1550 nm laser source which is modulated by microwave signals.And a photodetector is utilized to demodulate the microwave signals.The microwave transmission property of the switch is obviously observed by application of driving signals to the thermal heater.The simple SPP optical switch is very promising for high-density SPP waveguide integrations in integrated microwave photonics.