Abstract. Clinching is a versatile mechanical joining method for assembling different sheet metal materials without auxiliary elements in short process times. The joint strength, however, solely relies on the material condition and its targeted interlock formation. Therefore, accurate material models are necessary incorporating all relevant phenomena to reliably predict the material behaviour. We extend a finite elastoplastic material model by incorporating the plastic orthotropy of the sheet metal in the joining process simulation. The anisotropy is captured by different variants of the 3D Hill 1948 yield function with associative and non-associative plastic flow. The constitutive models and the 3D clinching simulation are outlined and utilised to study the influence of plastic orthotropy focusing on the aluminium alloy EN AW-6014.