The permeability plays a significant role during moulding of refractories. This parameter influences the time needed for the moulding procedure. The objective of this theses is the investigation of the permeability of refractories. In dependence of the material grain shape distribution, the moulding pressure and the binder differences concerning the permeability were determined. Furthermore the Young's modulus was determined by the sound transmission method. To avoid the laborious manufacture and testing of the samples it was tried to calculate the permeability with suitable models. The calculation models use different approaches to describe the flow resistance. The comparison between the calculated and the measured data shows obvious differences. The calculation models base on the idea that the permeability depends on the flow passages inside the samples. The porosity and the specific surface describe these passages. Furthermore the Sauter-diameter is needed for the calculation. The influence of the binder wasn't taken into account wether at the calculation of the Sauter-diameter nor at the determination of the specific surface. Due to that it can be concluded that the Sauter-diameter of the mixture is higher than the calculated one. To estimate the influence of the liquid binder on the specific surface, samples with different humidity were tested. The results show, that the liquid binder reduces the specific surface significant.