Scott Vernon's 10th goal of the season was enough to earn Aberdeen maximum points against struggling Dunfermline.
Iain Turner hesitated in coming to collect a long ball from Mark Reynolds and Vernon headed over the stranded goalkeeper on 24 minutes.
Prior to the breakthrough, Pars striker Liam Buchanan headed straight at Jason Brown from close range.
Brown saved from sub Joe Cardle two minutes from time as the Dons held on to move up to sixth in the SPL.
Dunfermline manager Jim McIntyre included Mark Kerr against the team he once captained, while the Dons' new midfielder, Stephen Hughes, started on the bench but played for the last 20 minutes in place of Fraser Fyvie.
And Kerr made a bright start at his old ground, picking out Liam Buchanan whose deflected shot drifted wide for a corner.
The hosts carved out their first real opening after six minutes when Rory McArdle crossed for Fyvie but Turner managed to tip the midfielder's low shot past the post.
Dunfermline should have broken the deadlock after 13 minutes when David Graham's perfect cross picked out the unmarked Buchanan but the striker's header was straight at Brown.
The Dons almost capitalised when Turner flapped at a Fyvie cross after 20 minutes but Reynolds' header just cleared the crossbar.
Aberdeen made the breakthrough after 24 minutes when Reynolds picked out Vernon with a hopeful pass upfield and the Englishman's first-time header looped over the badly positioned Turner and into the unguarded net.
Turner did well to block a Chris Clark drive, which took a wicked deflection, just before the break.
The Dons looked eager to put the result beyond doubt in the early stages of the second half with Clark Robertson firing well over and Vernon outpacing Kevin Rutkiewicz but his angled shot was well handled by Turner.
The hosts wasted another opportunity on the hour mark when they were awarded a free-kick in an inviting position but Turner was equal to Kari Arnason's weak, low drive.
However Dunfermline were enjoying large chunks of possession with Graham proving a particular nuisance to the Dons rearguard.
In a bid to stem the Pars' attacks, Dons manager Craig Brown introduced Hughes for his debut and Mohamed Chalali for Magennis and Fyvie after 69 minutes.
The Pars introduced Andy Kirk and Cardle for Willis and Buchanan with 11 minutes remaining as Dunfermline pressed for the equaliser.
And it was Cardle who should have earned his side a point two minutes from time when he latched onto McArdle's slack backpass but Brown denied the Dunfermline substitute to ensure the Dons held out for the win.