In this article, we consider a non-smooth multiobjective fractional semi-infinite optimization problems with equilibrium constraints. The concept of \(S \) -stationary point is stated in terms of Clarke subdifferential for the non-smooth multiobjective fractional semi-infinite optimization problems with equilibrium constraints. Under the \(S \) -stationary point and \(E \) -convexity assumptions, we developed an \(E \) -sufficient optimality condition for the considered model. Additionally, we have formulated the \(E \) -Mond-Weir and \(E \) -Schaible type dual models, and further, \(E \) -weak, \(E \) -strong, and \(E \) -converse duality results are established for the proposed dual models under \(E \) -convexity assumptions and using the idea of \(S \) -stationary point. Moreover, the theoretical results of the work are also validated by citing non-trivial example.
