The experienced midfielder joins on loan until the end of the season having previously played for the Daggers in 2009.
At the time, the club were in League Two and Loft says he can't wait to get started.
"I enjoyed my time here last time and I'm looking forward to playing here again," he told the club's website.
He's since been at Port Vale and Colchester United before linking up with current club Shrewsbury Town, expereince that Daggers boss Peter Taylor says could prove invaluable.
He said: "I'm really pleased to have signed Doug Loft on loan until the end of the season, he is a very experienced midfield player that I felt we needed and I'm really pleased to have him on board."
Loft could feature for the Daggers in their National League game with Aldershot Town on Saturday.