|Wigan Warriors (6) 12|
|Tries: Williams, Isa Goals: Smith 2|
|Hull FC (2) 16|
|Tries: Michaels, Talanoa Goals: Sneyd 4|
Fetuli Talanoa punished Wigan's Dom Manfredi for a costly fumble in goal to help Hull FC reach their second Challenge Cup final in four years.
Wigan's George Williams darted over for the game's first try, with Marc Sneyd's penalty making it 6-2 at half-time.
Matty Smith added to Wigan's lead with a early second-half penalty, only for Steve Michaels to hit back and Talanoa to pounce on Manfredi's error.
Willie Isa pulled a try back for Warriors, but Hull held on to progress.
The Black and Whites will face the winner of Saturday's semi-final, which will be between Warrington and Wakefield, at Wembley Stadium on 27 August.
Wigan, who beat Hull 16-0 in the 2013 final, went ahead after 17 minutes as Williams threw a dummy before sneaking past Gareth Ellis.
It was the only defensive lapse from either side in an uncompromising first half, dictated by the guile and boots of Hull's Sneyd and Wigan's Smith.
Sneyd teed up Hull's only points of the first 40 minutes, but the Super League leaders were denied a further score by Sam Tomkins as he pulled Ellis up just short of the line - with the video referee eventually ruling out the effort.
A forward pass from Oliver Gildart to send Lewis Tierney in for a second Wigan score before the break would prove key as Michaels and Talanoa went over for two unanswered tries in four second-half minutes after Smith had landed a penalty for Warriors.
Hull refused to relinquish the lead that Talanoa gave them, running in unopposed to touch down after Manfredi allowed a high and seemingly innocuous high kick from Sneyd to slip though his hands.
Despite losing hard-running centre Mahe Fonua following a head knock, man of the match Sneyd added to Hull's lead with his second penalty, while late pressure from Wigan yielded only Isa's score nine minutes from the end.
Hull 'had to do it tough'
Wigan Warriors head coach Shaun Wane told BBC Sport: "They were the best team, but I would say I'm very proud of our efforts.
"People don't understand how busted we were but the effort of that group of 17 players was outstanding.
"Hull were the best team, they deserve to be at Wembley and all the best to them."
Hull FC head coach Lee Radford: "I'm really pleased. There wasn't a great deal between the sides.
"It really was who wanted it most towards that back end and I just felt we had that little bit extra."
Hull FC captain Gareth Ellis: "You sometimes think that these opportunities aren't going to come. We've been outstanding all year and we were outstanding tonight.
"The effort we showed, particularly in defence by our try line, was outstanding. Wigan are a top side and we had to do it tough tonight."
Wigan Warriors: Tomkins; Tierney, Gildart, Sarginson, Manfredi; Williams, Smith; Flower, Powell, Sutton, Isa, Bateman, O'Loughlin.
Interchanges: Crosby, Mossop, Tautai, Bretherton.
Hull FC: Shaul; Michaels, Fonua, Yeaman, Talanoa; Tuimavave, Sneyd; Taylor, Houghton, Watts, Minichiello, Manu, Ellis.
Interchanges: Green, Thompson, Pritchard, Washbrook.
Referee: Ben Thaler