Union Berlin sack coach Bjelica amid Bundesliga survival fight
The club fell 4-3 at home to Bochum on Sunday to sit 15th in the Bundesliga, one-point ahead of Mainz who occupy the relegation play-off spot.
Grote, 51, will work alongside current assistant coaches Marie-Louise Eta and Sebastian Boenig with the next league game against relegation rivals Cologne on Saturday.
"I'm convinced that we'll manage to avoid relegation," said Grote.
Bjelica, 52, was appointed last November after the capital club parted ways with coach Urs Fischer following a nine-game league losing run left them in last place.
Grote had been in charge of Union's U19s in the A-Junior Bundesliga since July 2022, and stepped in on an interim basis in November, breaking the team's losing streak with a 1-1 draw against Augsburg.
In the top division since 2019, Union Berlin finished fourth last season and were playing Champions League football against Real Madrid as recently as December.
Union Berlin's final game of the campaign will be at home to seventh-placed Freiburg on May 18.