In this paper, an application of artificial neural network based on multilayer perceptron (MLP) model is presented for predicting the slot size on the radiating patch for improvement of the performance of patch antenna. Several performance affecting parameters like resonance frequencies, gain, directivity, antenna efficiency, and radiation efficiency for dual band frequency are observed with the variation of slot size. For validation of this work, a prototype X-shaped patch antenna is fabricated using glass epoxy substrate and its performance parameters are measured experimentally and have been found in good agreement with ANN and simulated values.