Pneumatic tyre tread comprising at least one circumferential groove; at least two ribs adjacent to the circumferential groove; and resonators which are formed with a groove shape in which one end opens into the circumferential groove and the other end terminates in a rib and which reduces air column resonance in the circumferential groove; in the resonators, a plurality of branch groove sets are formed in the circumferential direction of the tyre in such a way that the branch grooves of one set do not come into contact with each other on the same rib, each set of branch grooves including at least a first branch groove having a first opening which opens into the circumferential groove and a first end part which terminates in the rib, and a second branch groove having a second opening which opens into the circumferential groove and a second end part which terminates in the rib, the pneumatic tyre tread being characterized in that: the length L41 of the first branch grooves of the resonators is at least 40% of the length L of the contact surface measured in the circumferential direction, and the groove width W41 is between 10% and 25% of the groove width W of the circumferential groove, when the tyre is mounted on a standard rim and inflated to the nominal inflation pressure, and the nominal load is applied; the length L42 of the second branch grooves of the resonators is between 40% and 90% of the length L41 of the first branch grooves, and the groove width W42 is no less than the groove width W41 of the first branch grooves, when the tyre is mounted on a standard rim and inflated to the nominal inflation pressure, and the nominal load is applied; the first openings of the first branch grooves of the resonators and the second openings of the second branch grooves open from the same rib into the same circumferential groove and also grooves of each branch groove set with its corresponding opening to the circumferential groove are alternately disposed in the direction of rotation of the tyre; the first branch grooves of the resonators are formed in such a way that the length between adjacent first openings which open from the same rib into the same circumferential groove constitutes no more than 50% of the length L of the contact surface measured in the circumferential direction, so that the whole of a first branch groove is present within the tread contact surface; and the difference between the minimum cross-sectional void ratio in the rib where the first and second branch grooves (41, 42) of the resonators are formed and the maximum cross-sectional void ratio in said rib is no greater than 10%. the length L41 of the first branch grooves of the resonators is at least 40% of the length L of the contact surface measured in the circumferential direction, and the groove width W41 is between 10% and 25% of the groove width W of the circumferential groove, when the tyre is mounted on a standard rim and inflated to the nominal inflation pressure, and the nominal load is applied; the length L42 of the second branch grooves of the resonators is between 40% and 90% of the length L41 of the first branch grooves, and the groove width W42 is no less than the groove width W41 of the first branch grooves, when the tyre is mounted on a standard rim and inflated to the nominal inflation pressure, and the nominal load is applied; the first openings of the first branch grooves of the resonators and the second openings of the second branch grooves open from the same rib into the same circumferential groove and also grooves of each branch groove set with its corresponding opening to the circumferential groove are alternately disposed in the direction of rotation of the tyre; the first branch grooves of the resonators are formed in such a way that the length between adjacent first openings which open from the same rib into the same circumferential groove constitutes no more than 50% of the length L of the contact surface measured in the circumferential direction, so that the whole of a first branch groove is present within the tread contact surface; and the difference between the minimum cross-sectional void ratio in the rib where the first and second branch grooves (41, 42) of the resonators are formed and the maximum cross-sectional void ratio in said rib is no greater than 10%.