The study of speech motor control from kinematic and acoustic signals collected from speakers requires an evaluation of the influence of the physical properties of the speech apparatus on the time variations of these signals. For this purpose, a 3D biomechanical tongue model is currently being developed at ICP. It is based on a 3D Finite Element mesh, in which 10 different tongue muscles are represented. The non-linear elastical properties of human tongue tissues are accounted for with hyperelastic characteristics and a large deformation modeling framework was chosen to accurately describe non-linear geometrical changes. The model is embedded in a realistic 3D geometrical description of the jaw and of the vocal tract walls, which are both considered as fixed and non deformable at the current stage of the model's development. In this paper, each modeling step is described and the impacts of the main tongue muscles on tongue shapes and vocal tract geometry are assessed through a number of various simulations. Their potential influences on speech motor control are discussed in the final section.