Abstract: SnO₂-K₂O-LiZnVO₄ system nanometer powers were prepared by co-precipitation.The influence of the liquid-doped K⁺ on the humidity-sensitive characteristics was studied.The conductance mechanism of the material is analyzed by direct current.The experimental results show that a humidity-sensitive material with lower resistance at lower humidity and with proper humidity sensitivity can be made by appropriate liquid-doped K⁺.The analysis of the characteristics of direct current shows that the material conductance is electronics-ion and the properties of the material are better with more composition of ion conductance.