Lopes, 20, joins for an undisclosed fee and has signed a three-year contract which includes a club option of a further year.
The move sees Lopes link up for a second time with Head Coach Grant McCann, with the pair having previously worked together at Peterborough United.
Lopes is a product of the Posh Academy and, despite his young age, already has well over a century of senior appearances under his belt.
After joining Wigan last summer, he spent the second half of last season on loan at Gillingham where he played alongside another of the Tigers’ recent signings, Tom Eaves.
“I’m really excited to be here and I’m really looking forward to working with Grant McCann again,” said Lopes after signing for the Club.
“I’m still young and I still have a lot to learn, but I believe that Hull City is the right club to help me do that and I am looking forward to my future here.”