Considering accurate constitutive models is of the utmost importance to capture mechanical response of soft tissue and biomedical materials under physiological loading conditions. This paper investigated the behaviour of porcine myocardium of passive rested hearts. This was investigated by applying biaxial loads on the myocardium. The main objective of this research was to investigate the cardiac mechanics of various regions in the healthy passive of a porcine. The biaxial mechanical properties of myocardial tissue samples were captured using a biaxial testing system. The porcine heart was divided into three regions, namely: left ventricle (LV), septum and right ventricle (RV). In these regions, 18×18 mm2 equal samples were cut from six porcine passive hearts. For the LV sample, biaxial elastic modulus in the fibre direction is 33.3% larger than in the cross fibre direction. For the mid-wall sample, biaxial elastic modulus in the fibre direction is 18.8% larger than in the cross fibre direction. For the RV sample, biaxial elastic modulus in the fibre direction is 33.3% larger than in the cross fibre direction. It was concluded that the cardiac mechanics of LV, Septum and RV exhibit different mechanical behaviour. The mechanical behaviour exhibited by various regions (LV, Septum and RV) in the healthy porcine heart differs considerably. To develop adequate computational models, these data could be utilized to estimate the material parameters of the myocardium.