Abstract. In this work, a new extension of the exponentiated Weibull model is introduced with its mathematical properties and applications to failure times and medical data using the maximum likelihood method. We assess the per- formance of the maximum likelihood estimators in terms of biases and mean squared errors by means of a simulation study. We prove empirically the im- portance and zexibility of the new model in modeling two types of lifetime data. We conclude that, the new model is much better than the Weibull , expone- tiated Weibull, beta Weibull, Kumaraswamy Weibull, Transmuted Weibull, Weibull generalized Weibull and McDonald Weibul models in modeling failure times and breast cancer data.