An investigation about the robust estimation of a class of systems with noise coupling input saturation is presented in this study. In general, the existed estimation algorithm is based on the exactly known of the input saturation, but in fact, this is not always true in some practical cases because of the coupling of input saturations and input noises. For treating these kinds of coupling problems in the state estimations of systems, in this study, one fuzzy-based robust estimation algorithm is proposed. The proposed robust estimator includes two parts: firstly, a regression form fuzzy system that is adopted to approximate the unknown input saturation, and then, a robust estimator that combines the above fuzzy system by robust filter design concept for eliminating the effects of noises and modeling uncertainties is proposed. This combination of fuzzy approach and robust filtering technologies successfully offers one a more simple and practical method for treating the estimation problem of a class of systems that input saturations and input noises couple together.