This paper aims to show the three main estimators variance that have been proposed in nonparametric regression when you have a comment on the response variable And for every point on the independent variable X, which have been an essential tool to obtain an estimate parameter variance, they are the estimator Rice (1984), the estimator Gasser – Sroka y Jennen Steinmetz (1986) and the estimator Hall Kay and Tittetington (1990), all this with the aim of showing that both Parametric regression as a nonparametric regression is important addition to estimating the regression function, the estimate of variance, with the purpose of estimating and test characteristics of the role of regression.