Striker Youssef En-Nesyri scored the winning goal in the first half, leaping highest to beat goalkeeper Diogo Costa to the ball and heading in to spark pandemonium at Al Thumama Stadium.
The north African side’s supporters populated most of the venue and joyously celebrated their breakthrough moment on the global stage.
Ronaldo came off the bench in the 50th minute to equal the men’s all-time appearance record of 196 in international matches, but he could not drag his side back into the contest.
Morocco, who will face England or France in the last four, were happy to play on the counter and grabbed the opener just before the break when En-Nesyri headed in from Yahya Attiyat-Allah’s cross.
Portugal skipper Bruno Fernandes came agonisingly close to levelling just minutes later but a brilliant individual effort struck the crossbar.
Decimated by injuries, Morocco sat back for the majority of the second half and Yassine Bounou brilliantly tipped over Joao Felix’s drive – the closest they came to an equaliser.
Morocco striker Walid Cheddira was sent off for a second yellow card in eight minutes of additional time but Portugal could not find the equaliser as their last-four hopes were dashed.
Follow reaction from Morocco v Portugal
Magnificent Moroccans make history
Three African sides had previously reached this stage of the World Cup but none had progressed any further. Until now.
The marvellous Moroccan players and fans rejoiced as En-Nesyri’s header on 42 minutes proved to be the pivotal moment.
Fans whistled and jeered every pass the Portuguese players made and then the rowdiest section behind the goal seemed to suck the ball into the net.
Walid Regragui’s side were missing West Ham’s Nayef Aguerd, Bayern Munich’s Noussair Mazraoui and lost captain Romain Saiss to injury early in the second period.
But they defended resolutely and frustrated Portugal to keep their seventh clean sheet in eight games under their boss and have conceded just once in this tournament.
Morocco are a tough proposition and buoyed on by a partisan crowd in Doha, they will present a difficult challenge to whoever they face in the last four on Wednesday.
Goalkeeper Bounou, earning his 50th cap, pushed away a header from Felix early on and a deflected strike flew narrowly over.
Morocco had carved out the better opportunities on the break but En-Nesyri sent two free headers off target and Sofiane Boufal’s curler was straight at Costa.
In his desperation for an equaliser, Fernando Santos sent on Ronaldo early in the second half but the 37-year-old – who equalled Kuwait striker Bader Al-Mutawa’s international caps record – found it difficult to make any impact.
Having seen rival Lionel Messi reach the semi-finals on Friday, Ronaldo could not do the same with his side on what is likely to be his final World Cup appearance, trudging down the tunnel in tears at full-time as his dream was over.
Morocco
8.77
8.69
8.65
8.48
8.47
8.43
8.39
8.39
8.36
8.28
8.24
8.24
8.17
8.12
8.07
7.13
Portugal
4.43
4.36
4.35
4.32
4.28
4.18
4.17
4.08
3.89
3.82
3.81
3.68
3.62
3.61
3.57
3.28
Line-ups
Morocco
Formation 4-3-3
1Bono
2Hakimi18El Yamiq6Saïss25Attiat-Allah
8Ounahi4S Amrabat15Amallah
7Ziyech19En-Nesyri17Boufal
1Bono2Hakimi18El Yamiq6SaïssSubstituted forDariat 57’minutesBooked at 70mins25Attiat-Allah8Ounahi4S Amrabat15AmallahSubstituted forCheddiraat 65’minutesBooked at 90mins7ZiyechSubstituted forAboukhlalat 82’minutes19En-NesyriSubstituted forBenounat 65’minutes17BoufalSubstituted forJabraneat 82’minutes
Substitutes
9Hamdallah10Zaroury11Sabiri12Mohamedi13Chair14Aboukhlal16Ezzalzouli20Dari21Cheddira22Tagnaouti23El Khannouss24Benoun26Jabrane
Portugal
Formation 4-3-3
22Diogo Costa
2Dalot3Pepe4Rúben Dias5Guerreiro
10Bernardo Silva18Neves25Otávio
8Bruno Fernandes26Gonçalo Ramos11João Félix
22Diogo Costa2DalotSubstituted forRicardo Hortaat 79’minutes3Pepe4Rúben Dias5GuerreiroSubstituted forCanceloat 51’minutes10Bernardo Silva18NevesSubstituted forCristiano Ronaldoat 51’minutes25OtávioSubstituted forVitinhaat 69’minutesBooked at 87mins8Bruno Fernandes26Gonçalo RamosSubstituted forRafael Leãoat 69’minutes11João Félix
Substitutes
1Rui Patrício6João Palhinha7Cristiano Ronaldo9André Silva12Sá14William Carvalho15Rafael Leão16Vitinha17João Mário20Cancelo21Ricardo Horta23Nunes24António Silva
Live Text
Match ends, Morocco 1, Portugal 0.
Second Half ends, Morocco 1, Portugal 0.
Attempt missed. Pepe (Portugal) header from the right side of the six yard box is close, but misses to the right. Assisted by Rafael Leão with a cross.
Attempt saved. Zakaria Aboukhlal (Morocco) right footed shot from outside the box is saved in the centre of the goal. Assisted by Yahya Attiat-Allah.
Corner, Portugal. Conceded by Badr Benoun.
Second yellow card to Walid Cheddira (Morocco) for a bad foul.
João Félix (Portugal) wins a free kick in the defensive half.
Foul by Walid Cheddira (Morocco).
Walid Cheddira (Morocco) is shown the yellow card for a bad foul.
Pepe (Portugal) wins a free kick in the defensive half.
Foul by Walid Cheddira (Morocco).
Attempt saved. Cristiano Ronaldo (Portugal) right footed shot from outside the box is saved in the bottom right corner. Assisted by Bruno Fernandes with a through ball.
Offside, Morocco. Sofyan Amrabat tries a through ball, but Walid Cheddira is caught offside.
Vitinha (Portugal) is shown the yellow card for a bad foul.
Foul by Vitinha (Portugal).
Azzedine Ounahi (Morocco) wins a free kick in the defensive half.
Corner, Portugal. Conceded by Jawad El Yamiq.
Vitinha (Portugal) wins a free kick in the defensive half.
Foul by Achraf Hakimi (Morocco).
Foul by Ricardo Horta (Portugal).
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