Sintering ceramics have been widely used in industries which require electrical and mechanical properties. Thermal sprayed ceramics coatings are also applied for the industries, however the coating which has micron size pores are limited their applications due to inferior electrical and mechanical properties compared with sintering bulk. To expand thermal sprayed ceramics coating applications, dense coatings prepared by suspension plasma spraying are widely studied. Dense Al2O3 coatings are applicable to fabricating equipment for electronics devices, such as ESC. There are no reports regarding electric properties of plasma sprayed dense Al2O3 coating with different spray conditions. In this study to achieve a electric properties of dense Al2O3 coating, spray parameters such as plasma power, gas flow rate and spray distance are investigated. Suspension materials prepared with three microns Al2O3 powder are sprayed by high power suspension plasma spraying system. Spray conditions, plasma power, gas flow rate, and stand-off distance affect the coating density, crystal phase, and mechanical and electrical properties. Mechanism of coating formation by plasma spraying with fine powder suspensions will be discussed based on the findings. Al2O3 coatings obtained by the plasma spraying is applied for application to application utilizing the electrical insulation properties of such electronics devise manufacturing equipment components is proceeding.