Strzyzewski will be joined at the Moatmen by assistant Thom Kellogg and coach Lee Mitchell.
Strzyzewski replaces Carl Abbot, who was relieved of his duties following last month's 3-0 defeat at home to Bedworth United.
The club currently sit second-bottom in the Pitching In NPL Midlands Division, having picked up just five points from their opening eight league matches.
Strzyzewski is well-known to many at the Moat Ground, having made 89 appearances for the club between 2012-14.
He leaves former club Belper second position in the United Counties Premier Division North League - the club’s highest position in its history. He previously helped them to promotion via the play-offs in 2021/22.
He will take charge of the team for the first time on Saturday when they host Shepshed Dynamo.
Chairman Gary Norton said: “Marc was a standout candidate for the role for a wide variety of reasons, and we are delighted that he’s agreed to join us at the Moat Ground.
"Marc and his team are hungry and ambitious, and he’s demonstrated with the teams he’s managed to date an ability, within very modest means, to build squads capable of consistently outperforming and punching above their weight at the level they operate in.
“Marc impressed our selection panel during a rigorous interview process which comprised of two very detailed interviews.
"Those board members involved in the selection panel were unanimous in the decision to offer the job to Marc and his team.
“Marc’s hunger and ambition to develop a team to be proud of on the pitch very much matches the ambition myself and the club's board of directors have off the pitch for the years ahead."
Photo credit: Gresley Rovers