Highlights This review gives a thinking based on the generic mechanisms rather than simply dividing them as different types of combination of materials, which is unique and valuable for understanding and developing the novel hybrid materials in the future. The hybrid materials, their sensing mechanism, and their applications are systematically reviewed. Critical thinking and ideas regarding the orientation of the development of hybrid material-based gas sensor in the future are also discussed. Chemi-resistive sensors based on hybrid functional materials are promising candidates for gas sensing with high responsivity, good selectivity, fast response/recovery, great stability/repeatability, room-working temperature, low cost, and easy-to-fabricate, for versatile applications. This progress report reviews the advantages and advances of these sensing structures compared with the single constituent, according to five main sensing forms: manipulating/constructing heterojunctions, catalytic reaction, charge transfer, charge carrier transport, molecular binding/sieving, and their combinations. Promises and challenges of the advances of each form are presented and discussed. Critical thinking and ideas regarding the orientation of the development of hybrid material-based gas sensor in the future are discussed.