A series of upsets meant Jabeur was the only seed left in the tournament, but she was outfought by Halep, whose win-loss record in 2022 now stands at 11-1.
The result followed two years on from Halep beating Jabeur in the second round at the same tournament, on that occasion needing a third-set tie-break to get the better of the Tunisia. Halep went on to win the title on that occasion.
"It was a very tough match. Even if it's in two sets, it felt much harder than that," Halep said. "I had in my mind big time the match from 2020, it was so close and I knew I'd have to fight till the end."
Quoted on the WTA website, former Wimbledon and French Open winner Halep added: "I've been focused on what I have to do, and I wanted just to push Jabeur back because she has such a big game."
Halep will face Jelena Ostapenko in the last four after the big-hitting Latvian overcame Petra Kvitova 5-7 7-5 7-6 (11-9).
Kvitova led by a set and a break, and twice served for the match, yet Ostapenko prevailed to add the 2013 Dubai champion to the scalps of Sofia Kenin and Iga Swiatek this week.
Ostapenko, who triumphed in two hours and 39 minutes, has now reached at least the semi-finals in four of her last seven tournaments.
The other semi-final will be contested by Veronika Kudermetova and Marketa Vondrousova.
Kudermetova reached her third career WTA 500 semi-final after beating lucky loser Jil Teichmann 6-2 5-7 6-4 in two hours and 23 minutes.
Vondrousova, meanwhile, became just the third ever qualifier to reach the last four of the tournament thanks to a 7-5 6-4 win over Dayana Yastremska.