An antenna can be modeled as a two-port network using S-parameters. However, having individual antenna S-parameters is not sufficient for modeling an array of antennas as antennas exhibit mutual coupling. This article proposes a network model to represent an antenna array with mutual coupling. Using the proposed model, an N-element antenna array is modeled as a combination of two-port networks representing each element and an N-port network representing mutual coupling. Two techniques to calculate mutual coupling S-parameters are presented: a primary method using numerical solutions and an approximate method using approximate expressions. The proposed model was validated using four monopole arrays having different inter-element spacings, the number of elements, and non-identical antennas.