Phillips, 41, succeeds Steve Kittrick who left the Gladiators earlier this week.
He led Buxton to the play-offs last season, though left Silverlands after a disappointing start to this term.
Phillips said: “Matlock’s a big club with great tradition, it has great support and has some good players.
“It may bother some people (him being a former Buxton manager) on social media and I know we would have turned it around there.
“But that’s in the past and what I will say is that I will never shirk my responsibilities.
“I’ll be open and available to talk with the fans for after all, they’re the people that help pay our wages. Win, lose or draw, I’ll be there in the bar afterwards to meet fans and answer any questions they may have.”
He will watch from the stands as Matlock travel to Mickleover tomorrow (3pm). Goalkeeping coach Steve Shuttleworth will be in charge of the side assisted by sports therapist Mark Mullins.
Matlock chairman Tom Wright said: “We spoke to some really good candidates but we were all very impressed with Paul who came across extremely well showing great enthusiasm for the job and the club and we feel with his past record and vast experience of this division, he was the best man for the job.”