Davide Frattesi’s extra-time winner sent Inter through to the Champions League final, after a dramatic 4-3 victory at San Siro sealed a 7-6 aggregate success.
The Nerazzurri will contest their second showpiece in the space of three seasons following a classic tie between two of Europe’s heavyweights.
Inter broke the deadlock in the 21st minute when Denzel Dumfries sprung the offside trap and fed the returning Lautaro Martinez, who slotted into an empty net.
The Nerazzurri skipper was involved again as the hosts doubled their advantage in first-half stoppage time. He was deemed to have been fouled by Inigo Martinez following a VAR review, and Hakan Calhanoglu made no mistake from the penalty spot.
Barca came roaring back after the restart. Eric Garcia’s controlled volley halved the deficit, before a close-range Dani Olmo header – both from Gerard Martin crosses – levelled the tie on the hour mark.
Hansi Flick’s side completed the turnaround three minutes from time, and looked like they had booked their place in the final when Raphinha lashed the ball past Yann Sommer at the second attempt from close range.
However, in the 93rd minute, Inter rescued themselves and forced extra-time when Dumfries’ cross was expertly lifted into the roof of the net by Francesco Acerbi.
The hosts then edged their noses ahead in extra-time when, following strong centre-forward play by Marcus Thuram, Mehdi Taremi teed up Frattesi, who brilliantly found the bottom corner to send San Siro into ecstacy.
Barca pushed for the equaliser. Substitute Robert Lewandowski headed over and Lamine Yamal tested Sommer, but Inter held out to secure their spot in the May 31 showpiece.