A tire testing machine according to the present invention, which can measure both uniformity and dynamic balance of a tire T, comprises a spindle for driving the tire T to rotate about a vertical axis, a spindle housing which supports the spindle rotatably, and a rotating drum rotatable about an axis parallel to an axis of the spindle and movable toward and away from the tire T. The spindle housing is fixed to a base through a piezoelectric sensor so that it can bear a pressing force provided from the rotating drum. The piezoelectric sensor is disposed within a plane including the axis of the spindle and perpendicular to the pressing force. With this structure, dynamic balance of the tire can be measured accurately and easily.