Stephen McManus' first-half header was the difference between the sides as Stuart McCall's men got back to winning ways following two successive defeats to St Johnstone and Aberdeen.
McCall was able to bring James McFadden back into his team following a hamstring strain picked up on international duty with Scotland, while former Manchester City goalkeeper Gunnar Nielsen started in place of the injured Lee Hollis.
Hibernian caretaker manager Jimmy Nicholl was without captain James McPake due to suspension, but his side were the more threatening in the early stages.
Eight minutes in, Paul Heffernan put an effort wide following Kevin Thompson’s cross, and the former Kilmarnock man curled another shot off target a few moments later.
Nielsen was called into action to deny Heffernan again before the hosts took the lead against the run of play 22 minutes in, as McManus headed in Lionel Ainsworth’s corner.
Stuart Carswell almost doubled their lead in the 39th minute, but his powerful shot flew just wide as Hibs stayed in touching distance at the break.
Chances were rare in the first 20 minutes of the second period, but Nielsen was eventually forced into a save again as he tipped Liam Craig's strike around the post.
Hibernian controlled much of the second half, but the hosts remained solid at the back as opportunities continued to be hard to come by.
Motherwell made things harder for themselves in the 87th minute as Shaun Hutchinson received a red card for denying a goal-scoring chance, but the away side were unable to capitalise from the resulting free-kick.
Nicholl’s men piled on the pressure in the final minutes, but Motherwell held on to the slender lead to move above Aberdeen into third in the Premiership, while Hibernian remain seventh.
