Abstract: Ceramic bearings are widely used in the high speed machine,especially in the micro or small turbine engines.The bearing stiffness has a considerable influence on the dynamic characteristics of a rotor-bearing system.There were some databases of slide bearing dynamic characteristics.Rolling bearing stiffness is usually estimated empirically and it is simplified as a constant stiffness element.This method often causes large error.The primary factors that influence the rolling bearing equivalent stiffness were analyzed and a method for the calculation of rolling bearing equivalent stiffness was proposed.A test rig was designed for measuring the equivalent stiffness of ceramic bearings.The theoretical and experimental results agree well.