Trott, who was part of Britain's world-record breaking and gold-medal winning team pursuit trio at the London 2012 Olympics last summer, won the individual pursuit on day two in Anadia.
The 21-year-old qualified for the finals in first place with a time of 3:32.402 minutes and where she would face fellow Brit Elinor Barker, who was second less than three seconds behind.
Trott, who also won omnium gold at the London 2012 Olympics last summer, beat Barker by almost five seconds in the final however she is only just beginning in Portugal.
"It is nice to come back after the Olympics and see where I am at. It is nice to score some points towards World Championship places too," said Trott.
"From here I am doing other events, the scratch, the pursuit and the omnium, and then I will move onto the World Cup events."
- Sports & Recreation
- Elinor Barker
- London 2012 Olympics