Abstarct: Recently, with the development of science, humans need new techniques for research. X-rays can be used as an important tool in a variety of fields, including medicine, engineering, astronomy, chemistry and etc. X-ray is a kind of electromagnetic radiation that encourages scientists to study it and its uses. Therefore, we look at the production and characteristics of x-ray. The plasma focus device is one of the sources of x-ray production. In order to achieve the energy generated by nuclear fusion reactions and to prepare suitable conditions for thiese reactions, the need for the creation of plasma focus device has been maked, which has been a pulse generator of x-ray, neutron and charged particles that used in research and industrial centers for many years. The production of x-rays and neutron in this device requires the occurrence of a pinch in the system. The best efficiency of the device's products is when the pinch and maximum flow event simultaneously and the pinch has been symmetry and singularity. This device and x-ray emission of that, have advantages that make the device has abundant uses. The most important are high efficiency, low cost, easy maintenance and pulse x-ray emission from this device. In this study, we investigate the effect of gas type on x-ray doses emitted in a plasma focus device using thermoluminescence (TLD) dosimeters experimentally and theoretically. The pinch time parameter was also investigated at different pressures, voltages and gases. Analysis of data and diagrams shows that pinch time parameter increases with increasing pressure and decreasing with increasing voltage. According to the data obtained, the pinch time parameter at the same pressure and voltage as during the experiment with argon gas was higher than nitrogen gas was used. Experimental measurements of absorbed dose at different heights and absorption dose calculations of the detectors were performed theoretically by Monte Carlo method using MCNPX code. Experimental results show that the most X-ray emitted is in the range of tip height of the electrodes, which is in agreement with the simulation results. The x-ray dose is also higher when using nitrogen gas, which is consistent with the simulation results. The difference between this diagram and the corresponding diagram of the simulation data is in the intensity of the beam dose drop by the distance from the tip of the electrodes due to the inability to simulate electromagnetic forces and plasma in MCNPX software. Experimental results from the angular distribution show that most X-rays are propagated at an angle of 30° at a distance of 6 cm from the anode axis and the dose is anisotropic. The simulation results show that the absorption dose decreases with increasing distance from the spring. Also, the absorption (experimental) dose of the detectors was recorded outside the chamber at the background radiation level (near zero) and at zero simulation.