A heavy duty pneumatic tire comprising: a tread having at least three circumferential grooves formed thereon; a pair of sidewalls each connected to an end of the tread ; a pair of beads each located radially inward of the sidewall ; a carcass located inward of the tread and the pair of sidewalls and extending on and between a first bead and a second bead out of the pair of beads ; a reinforcing layer located radially inward of the tread ; and a buffer layer located radially inward of the reinforcing layer and formed from a crosslinked rubber, wherein among the at least three circumferential grooves , a circumferential groove located on each outer side in an axial direction is a shoulder circumferential groove , the reinforcing layer includes a belt including a large number of belt cords aligned with each other, the buffer layer is stacked on the carcass , each end of the buffer layer is located axially outward of an end of the belt , the belt includes a first belt ply stacked on the buffer layer , a second belt ply located radially outward of the first belt ply , and a third belt ply located radially outward of the second belt ply , the buffer layer includes a sheet portion and a pair of hump portions located axially outward of the sheet portion and thicker than the sheet portion , and each of the pair of hump portions has a maximum thickness (Tb) at an end of the first belt ply , characterized in that a nominal aspect ratio of the heavy duty pneumatic tire is not greater than 65%, the reinforcing layer further includes a band including a helically wound band cord , and the hump portion is integrated with the sheet portion . a tread having at least three circumferential grooves formed thereon; a pair of sidewalls each connected to an end of the tread ; a pair of beads each located radially inward of the sidewall ; a carcass located inward of the tread and the pair of sidewalls and extending on and between a first bead and a second bead out of the pair of beads ; a reinforcing layer located radially inward of the tread ; and a buffer layer located radially inward of the reinforcing layer and formed from a crosslinked rubber, wherein among the at least three circumferential grooves , a circumferential groove located on each outer side in an axial direction is a shoulder circumferential groove , the reinforcing layer includes a belt including a large number of belt cords aligned with each other, the buffer layer is stacked on the carcass , each end of the buffer layer is located axially outward of an end of the belt , the belt includes a first belt ply stacked on the buffer layer , a second belt ply located radially outward of the first belt ply , and a third belt ply located radially outward of the second belt ply , the buffer layer includes a sheet portion and a pair of hump portions located axially outward of the sheet portion and thicker than the sheet portion , and each of the pair of hump portions has a maximum thickness (Tb) at an end of the first belt ply , characterized in that a nominal aspect ratio of the heavy duty pneumatic tire is not greater than 65%, the reinforcing layer further includes a band including a helically wound band cord , and the hump portion is integrated with the sheet portion . <EOS>