New highly-rated signing Jude Bellingham, Emre Can and Jadon Sancho showed up as Lucien Favre's stand-out selections in Dortmund's season opener in front of 10 000 spectators.
Dortmund were struck with an early set-back 19 minutes in as Felix Passlack entered in the place of Thorgan Hazard, who had gone down with an apparent hamstring injury.
Erling Braut Haaland still threatened to give the hosts the lead three minutes later following a scorching left-footed attempt, but it was steered away by the opposing rear-guard.
A well-weighted ball in the area by Bellingham ten minutes to the break connected with Gio Reyna, who leaned towards the right before finding the far corner for his first goal.
Sancho almost gifted the Black and Yellow brigade a second minutes later, but watched in agony as his solid looking header scraped over the top.
Dortmund doubled their advantage nine minutes from halftime after Haaland fired home his first of the season from the penalty spot following a foul on Reyna.
What followed was solid piece of goalkeeper from Monchengladbach goalkeeper Yann Sommer who denied Reyna from a promising position while Passlack had an effort cleared off the line.
Haaland put the visitors evening to bed after turning home Sancho's delivery to complete his brace following the latter phases of the match.
Monchengladbach looked for some sort of consolation towards fulltime, but the Black and Yellow closed shop for a winning start to their campaign.