The young reporter was killed "covering the battle" near the village of Al-Shura, south of Mosul, Al Sumaria TV said in a short news flash on its website.
The channel named him as Ali Raysan.
Iraqi federal and allied paramilitary forces were working their way up the Tigris Valley south of Mosul today, the sixth day of the offensive on Mosul.
The huge operation launched on Monday, Iraq's largest in years, involves tens of thousands of forces and is expected to last weeks.