Voice over Internet Protocol (VoIP) is one of the fastest growing applications over Internet. The quality of service of VoIP can be measured by ITU E-model which is a subjective measure. In this paper, the authors discuss a novel method using Artificial Neural Network (ANN) to predict quality on real time traffic. It overcomes the drawback of available methods. NN has learning capability, so it can adapt to changes in the network without any human intervention. Using this method, quality of voice can be calculated at receiving end without any reference voice signal.