Deandre and Darryl Hill were 18 and 21 years old when they robbed and fatally shot Abel Martinez Mejia, 41, a truck driver and father of four, as he bought a $5 burrito on Jan. 22, 2008.
According to evidence at their Alameda County Superior Court trial, Deandre Hill demanded Mejia's money at gunpoint and Darryl Hill, who also had a gun, shot him five times.
Both were convicted in October 2008 of committing first-degree murder during the course of a robbery and were sentenced in 2009 to life in prison without possibility of parole.
The convictions were unanimously upheld by a three-judge panel of the state Court of Appeal in San Francisco.
The panel rejected the brothers' appeal claims that they should have been tried separately and that there were errors in jury instructions at their trial.