Gordon Black, a 34-year-old US staff sergeant, was detained on May 2 in Russia's far eastern city of Vladivostok after an argument with his girlfriend, Alexandra Vashchuk, whom he had met while in South Korea.
He pleaded not guilty to threatening to kill Vashchuk but admitted he was partially guilty of taking the money, though out of necessity.
Black's defence argued in its appeal that the original verdict was illegal and unfair, and asked for a new trial, RIA reported.
According to Black's defence lawyer, the verdict did not rely on case materials, ignored evidence confirming Black's innocence, and incorrectly interpreted his actions towards the victim, RIA reported.
However, Judge Irina Balashova of the Primorsky Regional Court in Russia's far east dismissed his appeal.
"Leave the verdict unchanged and dismiss the appeal," said Balashova, according to RIA.
Black is among a group of Americans held in Russia on a variety of charges. Last week, dual Russian-American citizen Ksenia Karelina was sentenced to 12 years in prison after a Russian court found her guilty of treason for donating $US51.07 to a charity supporting Ukraine.
