The Gunners take on Barcelona in the European showpiece in Lisbon on Saturday (24.05.25) and is desperate to write her name into the history books of a club she has supported since she was a child.
Williamson told UEFA.com: "I've always dreamed about winning the Champions League with Arsenal. That would mean everything to me, because I think it's the hardest to achieve, and I'm proud to have been part of a team that gave back to the club in that way.
"It would mean the world. For my family, for all the years that I've spent here, to feel like I've given back in that way and left a mark on the history of the club - something that people will enjoy for years to come. I would be very, very proud."
Williamson believes that Arsenal's team spirit under coach Renee Slegers has been key on their run to the final.
She said: "One of our greatest strengths since Renee took over is the empowerment and the shared responsibility and accountability among the team. We are very self-aware, we know what we need to do as individuals, across the board. And I'm talking from players to background stuff: everybody pulls their weight, which I think is really important.
"I think that's why we're in the Champions League final, because we have the attributes, we deserve to be there. Our performances have been incredible, to get us to where we are."
Arsenal are underdogs against Barca - who are bidding to win their third straight continental crown - but Williamson is expecting a fascinating match.
The England captain said: "They're a fantastic team and they've obviously got the recent history to prove it. We respect them a lot, but it's a final, so everybody turns up and everybody gives their best. We have lots of players who have been involved in different finals over their careers.
"I think it will be a good game of football. Barcelona are obviously notorious for their style of play; we're obviously a little early in our journey with Renee, but I think we're trying to build something, and it's always an interesting game when two teams like that come up."