In the optical communication system,the nonlinear optical thresholding de vice is an effective way to estimate the noise and enhance the performance of system.The supercontinuum(SC) -based optical threshold device has a simple structure and stable performance.For different application requirements and optical communication systems,we propose a novel tunable optical thresholding device that changes i ts thresholding performance by tuning the filter.In the experiment,when the optical signal power is 21.0dBm which is injected to the highly nonlinear fiber (HNLF),we can get the best 20dB bandwidth of 12~18nm for a fi xed central wavelength,and the best central wavelength of 1576nm for a fixed bandwidth.