Converting measured horizontal global solar irradiance in tilted ones is a difficult task, particularly for a small time-step and for not-averaged data. Conventional methods (statistical, correlation, ...) are not always efficient with time-step less than one hour; thus, we want to know if an ANN (Artificial Neural Network) is able to realize this conversion with a good accuracy when applied to 5-min solar radiation data of Bouzareah, Algeria. The ANN is developed and optimized using two years of solar data; the nRMSE (relative root means square error) is around 8% for the optimal configuration, which corresponds to a very good accuracy for such a short time-step. (C) 2014 Elsevier Ltd. All rights reserved.