In this work, the artificial neural network (ANN) is implemented for prediction slug frequency F-S for low viscosity mu(L) flow (mu(L) <= 1.6 mPa.S) in vertical, horizontal, and inclined pipes. To the authors' knowledge, no ANN model in the literature exists for predicting F-S. The input parameters for the suggested ANN are superficial liquid velocity V-SL, pipe diameter D, superficial gas velocity V-SG,V- and pipe inclination phi. Measured data (450 data points) are gathered from five different resources for developing the ANN model. The ranges of F-S, V-SL, D, V-SG, and phi covered by the data set, are (0.03 to 3.167 Ifs), (0.05 to 2.073 m/s), (0.01905 to 0.0779 m), (0.133 to 11.84 m/s), and (0 to 90 degrees), respectively. The most popular transfer functions of tangent sigmoid and linear are used in the hidden and output layers, respectively, whereas the Levenberg and Marquardt back propagation algorithm is conducted to train ANN. The experimental data set is divided into 70% for training, 15% for validation, and 15% for testing processes. Due to the absence of a systematic way to find the optimal structure of ANN, an exhaustive search method has been suggested and implemented to find the optimal topology, which is (4-16-1); four neurons in input layer, 16 neurons in the hidden layer, and one neuron in output layer. The proposed ANN predicts correctly the effect of each of the previously mentioned parameters on F-S, and it yields a satisfactory prediction and clearly outperforms all the existing models, with a mean square error (MSE) and R-2 of 0.0097 and 0.977, respectively.