Vazquez was sent to the stands after clashing with the fourth official late on in last weekend's 3-2 La Liga victory over Real Zaragoza and was subsequently handed the suspension.
He appealed but Friday's decision went against him, with the coach telling elidealgallego.com: "It's incredible. I was not expecting to be sanctioned. I think this case is alarming."
The 58-year-old will now have to sit in the stands for Saturday's trip to Levante and for next weekend's home meeting with Athletic Bilbao.
Depor have had some success on the disciplinary front this week, though, with captain Manuel Pablo available after the yellow card he received against Zaragoza, which would have triggered a ban, was chalked off.
The full-back has recovered from a knee problem and will play but the visitors will be without 12-goal top scorer Riki, who has a muscle strain.
Vazquez does, however, have Javier Camunas, the Brazilian duo of Evaldo and Kaka and Jesus Vazquez available as Depor seek a fourth consecutive win.
The run of results has lifted the club to 18th and within a point of safety ahead of tomorrow's encounter with 11th-placed Levante.
In contrast, the Valencia outfit have won only once in their last nine games, picking up seven points, and they lost 5-1 to Real Madrid last time out.
That has dropped Levante out of the reckoning for a European place but they do have defender Juanfran available after concern over a knee problem.