ATO/TiO2 coated by Sb-doped SnO2, and conductive composite powders were prepared by wet chemical method. AT0/Ti02 conductive composite powders were characterized by differential thermal-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) , scanning electron microscopy (SEM) and conductivity test. The research results were the influence of the calcination temperature on the SnO2 crystallization degree, the Sb valence, the conductivity of the ATO/TiO2 conductive powder were found. Resistivity - temperature (p-T) relations was the U-curve (100-900 ℃). During the uphill (150-400 ℃), temperature increased, amorphous SnO2 crystallized gradually, and the conductivity increased, Sb3+ → Sb5+ , carrier concentration increased, the porous structure of coating layer gradually densed; during the platform at the bottom (400-600 ℃), .the crystallization of SnO2 ended up, Sb3+ → Sb5+ change tended to completion, electron scattering tends to a minimum, the resistivity was the lowest, the conductivity was optical. During the downhill sections (600-900 ℃ ), Sb3+→ Sb5+ change reversed, TiO2 matrix particles grow up sharply, the acute-type tended to rutile-type changes, the coated structure was damaged, the resistivity increased, the conductivity deteriorated.%用湿化学法在TiO2颗粒表面包覆ATO制得ATO/ TiO2复合导电粉；运用TG- DSC、XRD、XPS、SEM、和电导率测试等手段对ATO/TiO2导电粉进行了表征.结果表明:煅烧温度对SnO2的晶化程度、Sb的价态、ATO/TiO2导电粉的导电性产生影响.电导率—温度(lnσ-T)关系呈抛物线(100～900℃):上坡段(150～400℃),温度增加,无定形SnO2逐渐晶化,电导率增加,导电性上升,溶入SnO2的Sb3+→Sb5+转变,载流子浓度加大,包膜层多孔结构逐渐致密化；底部平台(400～600℃),SnO2晶化结束,Sb3+→Sb5+转变趋于完成,电子散射趋于最低,电导率最大,导电性达到最佳；下坡段(600～900℃),Sb3+→Sb5+转变发生逆转,TiO2基体颗粒长大,锐态型向金红石型转变,破坏包膜结构,电导率上升,导电性恶化.
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