The paper reviews the factors influencing the sensitivity of conductometric semiconducting metal oxide gas sensors. The gas sensing process is closely related to surface reactions, which are influenced by various parameters such as chemical composition, surface modification, microstructure, temperature, and humidity. Composite materials, noble metal additives, and specific microstructures are highlighted as effective strategies to enhance sensitivity. Noble metals, due to their high catalytic activity, can improve sensitivity through the "spillover effect." The microstructure, including grain size and crystallographic facets, plays a crucial role in enhancing sensitivity and stability. Humidity and temperature also significantly affect sensor performance, with humidity decreasing sensitivity and requiring high temperatures for recovery. The paper concludes by emphasizing the importance of these factors in optimizing the sensitivity and reliability of metal oxide gas sensors.The paper reviews the factors influencing the sensitivity of conductometric semiconducting metal oxide gas sensors. The gas sensing process is closely related to surface reactions, which are influenced by various parameters such as chemical composition, surface modification, microstructure, temperature, and humidity. Composite materials, noble metal additives, and specific microstructures are highlighted as effective strategies to enhance sensitivity. Noble metals, due to their high catalytic activity, can improve sensitivity through the "spillover effect." The microstructure, including grain size and crystallographic facets, plays a crucial role in enhancing sensitivity and stability. Humidity and temperature also significantly affect sensor performance, with humidity decreasing sensitivity and requiring high temperatures for recovery. The paper concludes by emphasizing the importance of these factors in optimizing the sensitivity and reliability of metal oxide gas sensors.