Abstarct: The development and manufacture of carbon dioxide sensors is an important step in supervision the environment and air pollution, as well as controlling its concentration has applications in medicine and the food industry. Detection of carbon dioxide gas has been done using different types of sensors such as electrochemical, non-scattered infrared, solid electrolyte, surface sound wave, etc. These methods have technological and economic disadvantages for practical applications. Meanwhile, gas sensors baxsed on mextal oxide semiconductors have been seriously studied due to their excellent sensing properties, low cost, long life and the possibility of minimizing it. To make a sensor material, zinc oxide (ZnO) used due to the special properties of semiconductor mextal oxide such as simplicity in synthesis and fabrication, cost-effectiveness and excellent sensing properties against various oxidizing and reducing gases,etc. The synthesis of the sensor material was performed using the combustion method and to investigate the effect of catalysts on the parameters and characteristics of the sensor, different percentages of silver ( 0/02% and 1%) and nickel (5 and 10%) were added to zinc oxide during the synthesis process. Analysis of images taken by SEM and analysis of XRD data shows that the geometric properties of all made samples are nanorods in hexagona shape. The performance of the made sensor is evaluated by the parameters of sensitivity, response time, recovery, as exposed to carbon dioxide gas with concentrations of 0.5% and 0.75%. In terms of sensitivity and response time, doped samples showed better results than pure samples and without doping. Also, the highest sensitivity is related to the 5% nickel alloy sample.