Nigeria thus recorded an unassailable 11 points from five matches to go four points clear of second-placed Benin.
They welcome Rwanda to Uyo on Monday to wrap up their qualifying campaign.
Rwanda fell 1-0 at home to Libya earlier today in Kigali and this result effectively qualified Nigeria to Morocco 2025 even before the match against Benin.
Rwanda will now need to beat the Eagles in Nigeria to stand any chance of leap frogging Benin, while Libya will hope to beat Benin also on Monday and for the Super Eagles to beat Rwanda to stand any chance to sneaking through to Morocco 2025.
It was not a vintage performance by the three-time African champions, but they showed character by fighting back to hold home team Benin in Abidjan tonight.
Big Benin defender Mohamed Tijani scored his first international goal in the 15th minute against the run of play.
Nigeria drew level on 81 minutes through another header by Osimhen.
This was after he missed an open goal in the 41st minute for the biggest chance of the night.
The Eagles controlled the game from the first whistle with Alex Iwobi failing to put away a knockdown by Osimhen after nine minutes of action.
It was therefore against the run of play when Tijani was allowed a free header inside the Eagles box to give Benin a shock lead and his first international goal.
The goal appeared to have rocked Nigeria and Benin must blame themselves that they did not double their advantage late in the first half as they got the Eagles into all sorts of bother.
Caretaker coach Augustine Eguavoen made attacking changes at the restart with Moses Simon and Raphael Onyedika in for Kelechi Iheanacho and debutant Gabriel Osho, respectively.
It will pay off late on as it was Moses Simon cross that Osimhen headed home between two markers for the all-important leveler.
It was the striker’s 23rd international goal in 37 appearances to tie the legendary Segun ‘Mathematical’ Odegbami as the second most prolific scorer for Nigeria after Rashidi Yekini.