Isaac Roth (? - 2008) was a diamond dealer connected to the Jewish Mob.
Roth entered a deal with Pegorino Capo Ray Boccino to buy some diamonds. The deal, which took place at the Libertonian Museum, was ruined by Luis Fernando Lopez who had the deal shot up, killing Roth's partner Mori Green. After this disaster, Roth threatened to kill Boccino, as he claimed that Ray ripped him off. Ray then had Roth killed by Niko Bellic at the Majestic Hotel. Niko shoots Issac in the chest in Isaac's execution.