Cavitation is characterized by vapor bubbles creation in the liquid phase as a consequence of a pressure drop. This phenomenon can be reproduced by means of several two-phase models. An equation of state is commonly used in order to define the thermophysical properties of the two fluids and to close the model. The aim of this work is to study how the uncertain parameters of the equation of state (EOS) can influence the prediction of the cavitation structures. These uncertainties are propagated through a two-phase numerical solver for evaluating the impact on the predictive character of the numerical solution. The variability of the mixture velocity and the mixture pressure are analyzed. © Published under licence by IOP Publishing Ltd.