Rumours surfaced last week stating Zingarevich was ready to axe McDermott and bring in PSV Eindhoven coach Advocaat after the team's poor start to the season.
Dutchman Advocaat, 65, had a three year spell at Zenit St Petersburg, the hometown club of Zingarevich and the pair are believed to be friends.
But the wealthy Russian businessman insists McDermott has his total support, with funds available to spend in the January transfer window.
The news will be a welcome relief for McDermott who led Reading to their first Premier League victory of the season on Saturday with a 2-1 home win over high-flying Everton to move out of the relegation zone.
And Zingarevich was eager to set the record straight by denying the club had made contact with Advocaat.
"I don't know where that [rumour] came from, that's just speculation," declared Zingarevich. "As I said, there is nothing at all in that. Brian is the man for the job and I have total faith in him.
"Brian knows that everything is fine. We work as a team and we will continue to do that. He is the right man for the job and I am sure he will become a very good manager in the Premier League."
And when asked whether he was hurt by the speculation over McDermott's future, Zingarevich admitted: "Of course, because it is just unnecessary. I guess people will always speculate but for me it is a load of nonsense.
"For me, I have total faith in him, he has a long-term contract so I don't see any problem.
"Brian will be here in January. I think he had a little bit of an unfortunate start to the season but I'm sure it will pick up and everything will be fine.
"He has the right characteristics to be a good manager. You have to handle the group and the players and the manager is the key in that process.
"To be a good manager you need to be a good psychologist and I think he is. That was clear from the first meeting I had with Brian.
"We are trying to win every game which doesn't always happen. But we have a spirit amongst the players and staff which make me believe everything will be fine.
"We have a strong core here and I don't think we are in any sorts of trouble. I think everything is going okay."
McDermott was under increasing pressure after Reading failed to win any of their opening 10 Premier League games.
They were booed off the pitch at the end of last week's 0-0 home draw against Norwich City, with supporters suggesting it was time for McDermott to go.
But Royals broke their duck on Saturday when Adam Le Fondre scored twice against Champions League-chasing Everton.
Zingarevich declared: "Fans always get frustrated when results aren't going their way but they have to be patient a little bit.
"We did really well at the end of last season so the expectation is there.
"But The Premier League is tough. We've led in a lot of games a season and a couple of wins from those and everybody would be happy. That's football. We just have to learn from it and do better."
Reading now face back-to-back Premier League fixtures at Wigan Athletic this Saturday (3pm ko) then Aston Villa next Tuesday (8pm ko).
Winger Jimmy Kebe could return to the squad after missing the Everton game with a groin strain.
++ READING FC have teamed up with viagogo to provide season ticket Holders with the opportunity to resell seats for games they cannot attend.
In the past, fans who were forced to miss home games were forced to leave their seats empty. The new scheme gives them the chance to recuperate money for those fixtures they are set to miss out on.