K2O-SnO2-LiZnVO4 system humidity-sensitive ceramics are prepared by co-precipitation.The influence of the liquid-doped K+ on the humidity-sensitive characteristics is studied.The electric properties

conductance mechanism and equivalent circuit are studied by complex impedance analysis.The experimental results show that a humidity-sensitive material with 10% liquid-doped K+ is character of lower resistance at lower humidity and proper humidity sensitivity.Complex impedance analysis indicates that the capacitance of the sensor increases with relative hymidity（RH） up in especially for low measurement frequency.The material conductance is mainly electronics at low RH and ion at high RH.