Ex-swimmer Lauren Steadman continued her unbeaten record in the PT4 event, winning by almost three minutes.
Alison Patrick, who like Steadman has achieved the qualifying criteria for the Rio Paralympics, was victorious in her PT5 event.
Andy Lewis gave his Paralympic hopes a huge boost by winning the PT2 event, while Lizzie Tench claimed gold in the women's PT1 category in Portugal.
Tench's event is not part of the Rio programme.
Lewis, who was ranked 10th in the world coming into the event, beat the top two in the world rankings, Michele Ferrarin from Italy and France's Stephane Bahier.
The 33-year-old from Gloucester, who lost his leg after a motorbike accident when he was 16, put in a superb performance on the 5km run to claim victory.
"I don't know what to say," he told BBC Sport. "I've only been doing triathlon for 20 months. I left my job not knowing where it was going to go and I can't believe it."
There were also silver medals for Faye McClelland (PT4) and Melissa Reid (PT5) while Joe Townsend, who lost both of his legs while serving with the Royal Marines in Afghanistan, took bronze in the Men's PT1 event.
Britain have won four golds at the European Paratriathlon Championships.