Currently, ionic electro-active polymers (IEAP) using increases due to their interesting characteristics i.e., large strain response, soft actuation, similarities to biological muscles, . However, IEAP actuators have a complex behavior. This work presents a study on the modeling of an IEAP based trilayer actuator [PEDOT:PSS-PEO/NBR-PEO/PEDOT:PSS-PEO] using the bond-graph method which is a graphical approach based on energetic exchanges. As power is a universal currency in physical systems, it allows taking into account the electrochemo-mechanical phenomena and the interactions between them. The proposed model is able to predict the electro-chemical (current, voltage) and chemomechanical (force, displacement) behaviors of the actuator. Most relevant, with this model, simulation results are in good keeping with experimental ones. In addition, this model can be used to estimate physical values that could not directly be measured. This work is illustrated with simulation results and experimental validations