Pep Guardiola's side comfortably overcame Los Che and will look to the final in May as they look rectify last season's defeat against Real Madrid
With the cushion of Carles Puyol's away goal from the 1-1 draw at the Mestalla, the Catalans were in imperious form as Cesc Fabregas' first-half strike and a Xavi thunderbolt were enough to help Barca reach their 36th domestic cup final.
Barca struggled to settle in the early exchanges and Valencia were presented with a good chance to take the lead. Jeremy Mathieu's curling delivery found Sofiane Feghouli's darting run but the Frenchman's rasping drive was off target.
Despite their confident start, however, Los Che found themselves behind in the 16th minute when Lionel Messi's lofted pass caught Diego Alves in two minds. His indecisiveness allowed Fabregas to clip the bouncing ball past the keeper from an acute angle.
The Catalans should have doubled their lead when Messi intercepted Adil Rami's forward pass gave the Argentine a sight of goal, only for Diego Alves to parry his shot away. A stationary Valencia defence watched in desperation as Isaac Cuenca was first to react to the loose ball but the youngster skewed his effort wide.
But for Diego Alves, Valencia would have found themselves two goals down as their play continued to be littered with mistakes; the Brazilian stopper thwarted Fabregas twice with smart saves, as the visitors withstood heavy pressure.
Valencia started the second period strongly, though, and created a superb opening when Jordi Alba was played clean on goal. The Spaniard's touch took him away from the hounding Puyol and with his second he lashed the ball toward goal only to be denied by the legs of Jose Pinto.
Barcelona responded in kind. Messi demonstrated his supreme talent by evading four Valencia defenders with one sultry touch before bringing out a first-rate reactionary save from Diego Alves with a toe-poke that was heading for the corner.
The two players traded blows once more, but Messi was once denied by the Brazilian stopper leaving the striker with a look of disbelief on his face as his neat chip was deflected wide of the post.
At the other end, Puyol became Barcelona's saviour when he cleared ahead of the waiting Jordi Alba with an acrobatic clearance, while Pinto was forced to tip Jonas' thunderous drive over the bar soon after as Valencia began to attack relentlessly.
But their task progressed from improbable to impossible when Feghouli was shown his second yellow card leaving the visitors a man light and needing a goal in the remaining 13 minutes to keep alive their Copa del Rey hopes.
Soon after Aduriz had wasted a chance to level, Xavi destroyed any glimmer of hope with an emphatic finish following a swift Barca break. Diego Alves continued to deny Barcelona with a string of saves in the final moments, significantly a wonderful diving save from Messi's free-kick.
Pep Guardiola's side now have the chance to clinch their 26th Copa del Rey victory, and will meet Athletic Bilbao in May.