The 25-year-old goalkeeper came through the ranks at our fellow Women's Championship club and, after signing her first professional contract last summer, helped Sunderland to a third-place finish in the second tier.
With ten clean sheets to her name, as well as only conceding eighteen goals from 22 matches, Moan won the Golden Glove award to go along with her Player of the Season trophy.
On signing for Newcastle United Women, Moan said: "I am delighted to be joining Newcastle United, who have shown in the past two seasons that they are a very ambitious club.
"The set-up at the club is fantastic which is something I know will help me settle in very quickly.
"I will give everything I possibly can to the team and the fans, who I know give incredible support to the club. I can't wait to get started next week."
Manager Becky Langley added: "Claudia is a top goalkeeper and I worked with her previously when we won the league together at Northumbria University.
"Her stats from last season speak for themselves. The fact she won the Golden Glove and Player of the Season awards is absolutely fantastic when you look at the quality of players she was up against in that league. We're really excited to see her join the club."