All lanes of the H-1 Freeway heading west-bound are now open near the Waikele off-ramp, according to Honolulu police dispatch.
Police previously closed up to four lanes after a semi-trailer truck caught fire.
Officers arrived on scene at 4:09 p.m.
No injuries were reported, though most of the cab was blackened and destroyed.
Traffic remained at a standstill for hours through town.