Positron emission tomography (PET) is a nuclear medicine imaging technique that provides information on the human body’s operating system. This method uses positron-emitting radionuclides. The emitted positron inside the body combines with an electron and the annihilation phenomenon occurs, emitting two back-to-back photons with 511 keV energy. PET scanner consists of detectors which have the ability to detect and recording these two photons, coincidentally. By recording these photons as an electrical signal, several correction factors are applied to them. Using mathematical reconstruction algorithms, a three-dimensional (3D) image is obtained. Researchers are always trying to improve the quality of the reconstructed images. Choosing the type and size of the detectors and how they are arranged is one of the factors that affect the quality of the images In this study, the characteristics of different types of detectors used in PET scanners and their arrangements were investigated. Also, the specifications of PET scanners of different manufacturers were studied and finally the Monte Carlo model for Siemens Biograph Vision clinical PET scanner simulated. The GATE toolkit simulates and evaluates the performance of this model using the protocols of the National Electricity Manufacturers Association (NEMA NU 2-2018). By comparing the results obtained from the simulation and experimental results of the device, it was observed that there is no significant difference between the results. Validation of this simulated this model is the first step to achieving a more efficient device.