Johnson has lost 19 games due to a chronic knee injury, all 12 games of the 2009 season and the final seven games last season, when he was a senior co- captain.
The 6-foot-1, 215-pound Johnson, from Tumwater, Wash., earned All-Big Sky Conference second-team honors in 2010 when he started all 15 games of EWU's FCS championship-winning campaign. He has 260 tackles in his career.
"It's exciting and we're happy for Zach," Baldwin said. "He's worked hard since the day he got here and has been a hard worker all his life. He deserved to get a sixth year based on the injuries he suffered and what he's gone through. We couldn't be happier to have Zach back with us."
Eagles wide receiver Tyler Hart also is filing a similar appeal for a sixth season. He has been approved by the Big Sky Conference and needs approval from the NCAA.