Match ends, Manchester City Women 2, Arsenal Women 1.
Holders Manchester City reached the 2019-20 Women's FA Cup final with an impressive display against Arsenal.
Gareth Taylor's side will meet Everton at Wembley in 1 November's showpiece, live on BBC One, after the Toffees beat Birmingham City 3-0 on Wednesday.
Steph Houghton's curling free-kick put City in front before Jordan Nobbs levelled with a fine long-range strike.
But United States midfielder Sam Mewis quickly restored City's lead and they remained on top in the second half.
World Cup-winner Mewis' first goal in English football sent City through to the club's third Women's FA Cup final, all of which have come since 2017.
Record 14-time winners Arsenal had been bidding to reach their 17th final but were not able to reproduce the form they had shown in September, when they scored 19 times in three games in all competitions.
City bring Arsenal back down to Earth
Despite the Gunners arriving in Manchester in red-hot form, City dominated the ball for much of the game, especially in the first 25 minutes, and they were rewarded with Houghton's fine opening goal.
The England captain curled her free-kick through a gap in the Arsenal wall and narrowly inside the near post for her first goal since December 2019.
Against the run of play, Arsenal levelled when Nobbs hit a terrific, swerving strike from distance that beat Ellie Roebuck, five days after the midfielder had netted another fine individual goal with a lobbed effort in Saturday's quarter-final win over Tottenham.
But the Gunners were not on level terms for more than two minutes, as Chloe Kelly's cross was diverted by Ellen White straight into the path of Mewis to fire home from close range after she made a late, well-timed run into the box.
Replays showed the ball may have struck White on the arm in the build-up, but officials do not have the option of referring such an incident to a video assistant referee in this competition.
For Mewis to hit the winning goal was fitting, on a night when she controlled the midfield.
Physically strong, the United States star's height, presence and composure on the ball kept possession for the hosts for long periods and Arsenal's usually free-flowing side could not respond.
Her US team-mate Rose Lavelle came on for her City debut in the second half, after recovering from an ankle knock, and looked lively in the closing stages as the holders saw out the win relatively comfortably.
Yet it was in defence that the hosts were most impressive, as English quartet Lucy Bronze, Gemma Bonner, Houghton and Demi Stokes produced a compact, resilient display that ensured a quiet night for Arsenal's key striker Vivianne Miedema.
Sunday, 1 November's final [14:30 GMT kick-off] will be live on BBC One, when both City and Everton will bid to add to their two previous cup triumphs.
'No excuses' from Arsenal - reaction
Arsenal midfielder Jordan Nobbs told BBC Two:
"They dominated in the first half and were the better team. We didn't keep the ball very well at times but in the second half we showed we can play football and if we had played like that in the first half we would have been the better team.
"These are the games you have to win to go through and we didn't do enough tonight. Congratulations to Manchester City."
Arsenal boss Joe Montemurro:
"They dominated the first 60 minutes, they were better than us and we have no excuses.
"It's disappointing because we had the capacity to play well but tonight wasn't the night."
Man City boss Gareth Taylor told BBC Two:
"We played really well in the first half and I was really impressed with the performance and it could arguably have been a bigger lead going into half-time.
"Arsenal had a real good go in the second half and it was fairly tight at the end but we came through.
"It's good to be going back to Wembley, the girls really deserve it but we don't have time to stop with the WSL and the Continental Cup next week."
Man City Women
- 4BonnerBooked at 29mins
- 9KellySubstituted forParkat 80'minutes
- 18WhiteSubstituted forLavelleat 65'minutes
- 15McCabeBooked at 45mins
- 10LittleSubstituted forWältiat 50'minutes
- 7van de Donk
- Helen Conley
- Shots on Target
Second Half ends, Manchester City Women 2, Arsenal Women 1.
Attempt blocked. Katie McCabe (Arsenal Women) right footed shot from outside the box is blocked.
Katie McCabe (Arsenal Women) wins a free kick in the attacking half.
Foul by Gemma Bonner (Manchester City Women).
Beth Mead (Arsenal Women) wins a free kick in the attacking half.
Foul by Keira Walsh (Manchester City Women).
Foul by Katie McCabe (Arsenal Women).
Jessica Park (Manchester City Women) wins a free kick on the right wing.
Corner, Arsenal Women. Conceded by Caroline Weir.
Lia Wälti (Arsenal Women) wins a free kick in the defensive half.
Foul by Georgia Stanway (Manchester City Women).
Substitution, Manchester City Women. Jessica Park replaces Chloe Kelly.
Foul by Keira Walsh (Manchester City Women).
Katie McCabe (Arsenal Women) wins a free kick on the left wing.
Offside, Arsenal Women. Vivianne Miedema tries a through ball, but Katie McCabe is caught offside.
Attempt missed. Caitlin Foord (Arsenal Women) header from the centre of the box misses to the left. Assisted by Jordan Nobbs with a cross.
Corner, Arsenal Women. Conceded by Keira Walsh.
Attempt saved. Georgia Stanway (Manchester City Women) right footed shot from outside the box is saved in the bottom left corner.
Demi Stokes (Manchester City Women) wins a free kick in the defensive half.