Frank Rogue, 44, from Phoenix, faces death by lethal injection for gunning down Balbir Singh Sodhi, a Sikh, who wore a turban and beard as part of his beliefs.
Rogue had apparently mistaken Sodhi for being an Arab.
Prosecutors argued Sodhi’s murder on 15 September, 2001 was fuelled by racism and hate, and carried out by Rogue – a man with a long history of alcoholism.
But defence attorneys said Rogue was mentally ill and pushed over the edge by the attacks.
The jury deliberated for six hours, in the case which attracted international attention.
An appeal to the decision is mandatory.
"The jury brought justice back to our family. They brought the truth in front of the whole world and showed that we are all Americans"
Lakhwinder Singh Sodhi,
The shooting prompted India to call on the US government to take steps to prevent assaults on Sikhs living in America.
Sodhi, 49, who came to the US in 1988 from a small village in Punjab.
He was one of several Sikhs attacked in America after 11 September 2001 after apparently being mistaken as Muslims.
Rogue, who still faces sentencing on other charges stemming from two other shootings of people of Afghani and Lebanese descent on the day of the murder, becomes the 127th person on Arizona's death row.
Lakhwinder Singh Sodhi said he was relieved that more than two years of waiting was over and that his brother's killer will not go unpunished.
"The jury brought justice back to our family," he told Reuters.
"They brought the truth in front of the whole world and showed that we are all Americans."