"Am I sorry for not having gone to the gala? No. It was the right decision," Mourinho told RTP television.
"One, two or three people called me saying they had voted for me but the vote showed up as cast for somebody else. So, I decided not to go," he said.
The Portuguese coach and former Barcelona boss Pep Guardiola lost the 2012 FIFA coach award to Spain's Vicente del Bosque at January's gala.
FIFA said in a statement: "FIFA confirms that the list of votes published on FIFA.com is accurate."