Rutile Ti1xSnxO2(0.2x<1) solid solutions had been prepared using a sol-hydrothermal method, which combined the conventional sol-gel process with hydrothermal method. Hybrid alkoxides of Ti4+and Sn4+were used as precursors in the sol-gel process and Sn4+served as crystal-inducing agent during the formation of rutile crystal lattice in the hydrothermal process at 200°C. The microstructures and morphologies of nanoparticles were detected with XRD and TEM. Rutile Ti1xSnxO2solid solutions nanoparticles with well-distributed crystallite sizes about 10nm were obtained with Sn4+content above 20mol% without any high temperature calcination. The oxygen sensitivity properties of Ti1xSnxO2solid solutions had also been investigated. It is proved Ti1xSnxO2solid solutions exhibited higher oxygen responses than single TiO2or SnO2. A typical sample of Ti0.5Sn0.5O2presented the best sensitivity is approximately 6 under 400°C.