A probabilistic seismic demand model that relates ground motion intensity measures (IMs) to the structural demand measures is a useful tool for reliability analysis of structures. It is common to utilize the scalar seismic parameters or a vector of a few seismic parameters to reveal ground motion uncertainty. However, for the qualification of an IM for representing the ground motion uncertainty, a larger vector of greater seismic component is required. This study aims to use more parameters as vector IMs in the demand model to achieve better estimation of the ground motion uncertainty. In this study, three-layer feed forward neural network was used to predict the seismic demand model of the mid-rise RC buildings for pulse like ground motions. The results indicate that due to the complexity of the relationship between seismic response of structures and seismic intensity parameters, using artificial neural networks method is more suitable than numerical methods to show uncertainties.