Purpose: Cardiac SPECT imaging is widely used for many clinical practices such as the diagnostic of coronary artery diseases (CAD) and Myocardial Perfusion Imaging (MPI). In this work, we introduced the ProSPECT system, a dedicated cardiac SPECT system with open-gantry design. Materials and Methods: In this study we assessed the performance of the system based on NEMA-NU1-2007 standards. The ProSPECT system was characterized by measurement of planar, tomographic and clinical parameters. Results: Planar measurements showed 7.6 mm and 8.9% of spatial resolution and energy resolution at 140 keV, respectively. The tomographic resolution at 250 mm radius of rotation was 12.3 mm. Also, the maximum LOR and COR error for the tomographic imaging are obtained 1.1 mm and 1.8 mm, respectively. The clinical images that obtained using the system were confirmed by nuclear medicine physician expert. Conclusion: It concluded that the ProSPECT imaging is qualified for cardiac SPECT imaging.