A heavy duty tire comprises a tread portion provided with belt plies and circumferentially-extending main grooves, wherein a shoulder rib area between the axially outermost shoulder main groove and a tread edge is subdivided by a sub groove into an axially inner main rib zone and an axially outer sub rib zone. The main rib zone is provided with a high elastic modulus rubber layer extending along the axially outer edge of the main rib zone to form a part of the tread face and made of rubber having an elastic-modulus higher than that of rubber forming the tread face except for said part of the tread face. The axial width (W1a) of the high elastic modulus rubber layer is 0.3 to 0.6 times the axial width (W1) of the main rib zone.