A device for evaluating tire rolling resistance for a tire testing machine having a running drum , the device comprising: load rolls having surfaces that simulate a road surface on which a tire is to travel; a moving mechanism configured to move the load rolls alternately in an approaching direction in which the load rolls come closer to the tire and in a leaving direction in which the load rolls go away from the tire ; a load sensor configured to detect a load acting on the tire in a state where the surface of the load rolls are in contact with the tire ; a position sensor configured to detect a position of the load roll in a direction along the approaching direction and the leaving direction; a phase difference calculation unit configured to control the moving mechanism so that the load acting on the tire is varied and calculate a phase difference between a variation of the load and a variation of the position of the load roll on the basis of signals from the load sensor and the position sensor ; and a rolling resistance evaluation unit configured to evaluate a rolling resistance of the tire as an evaluation target by comparing the phase difference calculated for the tire as the evaluation target by the phase difference calculation unit with a phase difference calculated for a reference tire by the phase difference calculation unit , characterized in that the load rolls are two or more load rolls disposed side by side and are smaller in diameter than the tire , the load rolls are disposed separately from a tire testing machine for testing the tire , and the load rolls are disposed separately from the running drum of the tire testing machine . load rolls having surfaces that simulate a road surface on which a tire is to travel; a moving mechanism configured to move the load rolls alternately in an approaching direction in which the load rolls come closer to the tire and in a leaving direction in which the load rolls go away from the tire ; a load sensor configured to detect a load acting on the tire in a state where the surface of the load rolls are in contact with the tire ; a position sensor configured to detect a position of the load roll in a direction along the approaching direction and the leaving direction; a phase difference calculation unit configured to control the moving mechanism so that the load acting on the tire is varied and calculate a phase difference between a variation of the load and a variation of the position of the load roll on the basis of signals from the load sensor and the position sensor ; and a rolling resistance evaluation unit configured to evaluate a rolling resistance of the tire as an evaluation target by comparing the phase difference calculated for the tire as the evaluation target by the phase difference calculation unit with a phase difference calculated for a reference tire by the phase difference calculation unit , characterized in that the load rolls are two or more load rolls disposed side by side and are smaller in diameter than the tire , the load rolls are disposed separately from a tire testing machine for testing the tire , and the load rolls are disposed separately from the running drum of the tire testing machine . <EOS>