They fought back from a goal down against the four-time winners in Monastir to book a semi-final berth with hosts Tunisia on Wednesday.
Nigeria, winners in 1980 and 1994, were joined in the semi-finals by Morocco, who came back from the brink of elimination to beat Algeria 3-1 after extra-time in Sfax to set up a last four showdown with Mali.
Cameroon took the lead against Nigeria after 41 minutes through Samuel Eto’o, but the Super Eagles came back into the game four minutes later courtesy of skipper Austin “Jay Jay” Okocha’s sweetly-struck free kick from the edge of the box.
John Utaka finally won the game for Nigeria when he ran at the opposing defence before coolly slotting the ball past a diving Idris Kameni in the 73rd minute.
“Cameroon’s time has come and gone.
“With this victory everything has changed again and it is Nigeria’s time to reign supreme,” said Nigeria coach Christian Chukwu.
Cameroon coach Winfried Schafer said Nigerian organisation prevented his team from playing their usual game.
“I congratulate Nigeria. Sadly we conceded a goal right on half-time and just couldn’t find the net in the second half or play our usual game,” said the coach.
“But despite this defeat, Cameroon are still a team with great potential and the players will bounce back.”
Schafer, who also presided over a disastrous World Cup campaign in 2002 where Cameroon failed to make it past the first round, insisted he would not quit. “Why? Why should I leave?” he asked reporters. The win was sweet revenge for the Nigerians who have been denied three times by Cameroon in the final of the Nations Cup, in 1984, 1988 and 2000.
In Sfax, Youssef Hadji and Jawad Zairi scored extra-time goals as Morocco also came from behind to beat Algeria 3-1.
Abdelmalek Cherrad thought he had put the underdogs into a semi-final showdown against Mali in Sousse on Wednesday with an 84th-minute goal only for Marouane Chamakh to equalise four minutes into stoppage time.
Hadji then scored with an acute-angle shot under goalkeeper Lounes Gaouaoui in the 113th minute after leaving defender Samir Beloufa standing and Zairi sprung an offside trap to deliver the killer blow in the final minute.
“I think we deserved to win,” said Moroccan defender Oualid Regragui.
“We thought we were finished after they scored but then we hit the post at the end and we felt Algeria were there for the taking.”
Morocco were the third team after Mali and Nigeria to reach the semi-finals despite falling behind. However, the end of the match was marred by trouble on the terraces as angry
Algerian fans ripped up plastic seats and threw them on to the pitch.
Around 20,000 Algerian supporters had crammed into the compact Sfax ground where they were met by 2,000 members of the police and army.