The victory consolidated their dominance of the sport, with Germany having won every Olympic team dressage gold medal since hosting the Munich Games back in 1972.
The team scored 72.916 percent, thanks to a superb test from one of the legends of the sport, Isabell Werth on Satchmo.
The Netherlands won the silver medal with 71.750 percent. Denmark, emphasising Europe's domination of the event, took the bronze with 68.875 percent.
"We are so happy, the whole team were very excited to show a good competition," Werth told reporters after scoring 76.417 percent in her test. "A lot of people didn't believe in the German team after we lost the team gold in last year's European championships.
"The whole team were really helping each other and we have tried to get the best for everybody that was the key to our success," she said.
The victory came after Germany's sweep of the team and individual eventing gold medals earlier in the week, giving them three out of three in equestrian competitions at these Games so far.
But elsewhere, Germany's Olympic dreams were struggling. NBA star Dirk Nowitzki and the German basketball squad lost to 59 - 72 to Spain, putting the team under pressure to beat hosts China on Saturday to have any hope of reaching the quarterfinals.
Nowitzki criticized his performance of only 11 points - well below what he normally averages each game. "It wasn't enough. We didn't win, which means I didn't do my job," said Nowitzki.
Coach of the German national team Dirk Bauermann said his players knew facing China wouldn't be easy this weekend. "The Chinese play with an unbelievable amount of fire and passion, with the enthusiasm of the entire country behind them. It's going to be a very tough game," he said.