The Students' second league win of the season was a tad more convincing than the scoreline suggests, with a late Sligo rally and a patchy surface failing to blight a decisive performance.
UCD were one up within eight minutes when Robbie Benson made hay from Dean Marshall's corner, rising unmarked to head past a stranded Brendan Clarke.
It should have been more but Graham Rusk, Marshall and Benson failed to take opportunities that fell the home side's way.
But the Sligo rearguard gave way again in the 58th minute when Rusk hammered home after Darren Meenan's initial effort found its way out to him.
Matthew Blinkhorn gave the Bit O'Red some hope when his 83rd-minute shot was helped into the net by Michael Leahy, but it was too little too late for the visitors.
UCD -- Barron, O'Conor, Leahy, Haro, Nangle; Marshall, Creevy (Ledwith 63), Corry, Meenan, Benson, Rusk (Belhout 77).
Sligo Rvs -- Clarke, Keane, Peers, McGuinness, Davoren, Ndo (Greene 77), Ryan, Dillon (Horgan 61), Russell, Cretaro (Blinkhorn 69), Doyle.
REF -- G Kelly (Cork)