The 19-year-old is out of contract at the Westfalenstadion this summer, and will cost the Gunners around £600,000.
Eisfeld, who came through Dortmund's academy, has seen his progress hampered by a serious knee injury in 2009, but Arsene Wenger has seen something in the talented youngster that gives him confidence he can succeed at the Emirates Stadium.
The intention will be for Eisfeld to develop beneath the Arsenal first-team, with a view to continuing his development under the watchful eye of Wenger and his team of coaches.
Arsenal were also reportedly interested in German duo Lukasz Podolski and Mario Gotze, but neither player is expected to arrive in north London before the transfer window slams shut tonight.
With the club's hopes of UEFA Champions League qualification hanging in the balance, Gunners fans will be hopeful of some more deadline day activity to strengthen their push for a top-four finish.
However, it looks as though Eisfeld will be the only acquisition for Arsenal this month, meaning Wenger will have to make do with what he has got until the summer of 2012.