Hanlon powered in John McGinn’s corner in the 13th minute and though Anthony Stokes was frustrated in his efforts to add to their lead, one goal was enough.
Ex-Inverness striker Billy McKay was a threat on his first start for the hosts but Hibs held firm.
The Staggies, whose only league victory this season came on day one at Dundee, were looking to get back to winning ways following their 4-0 defeat at Celtic.
Joining McKay in the starting line-up were keeper Scott Fox, who became a father the day before, Reghan Tumilty and Craig Curran.
Lennon made three changes from the Hibs team which edged past Livingston 3-2 in the Betfred Cup quarter-finals in midweek. In came Steven Whittaker, Dylan McGeouch and Simon Murray, while captain David Gray was sidelined with a hamstring injury and midfielders Vykintas Slivka and Danny Swanson dropped to the bench.
These sides met earlier in the season when a goalless draw in the Betfred Cup finished with a County penalty shoot-out win.
The visitors looked lively from the start and Martin Boyle flashed a 20-yarder over the top after swift work along the face of the penalty box involving McGeouch and Stokes.
Their early pressure paid off when McGinn whipped in a corner and Hanlon cashed in on slack defending to bury the ball past Fox from close range.
Michael Gardyne then Ross Draper went close as the Highlanders probed for a swift leveller, but Hibs resisted some further pressure before Simon Murray’s deflected shot on 28 minutes was gathered by Fox.
County were still a threat and Tumilty found space on the right and sent in a cross which Gardyne touched on to McKay, but Ross Laidlaw was on hand to save.
Hibs could have increased their advantage early in the second half but Fox pawed away a goalbound 25-yard free-kick from Stokes.
On the hour mark, County were so close to levelling as McKay steered a cross in from the left and Gardyne went for goal, but Laidlaw superbly touched it on to the post and the danger was averted to keep Hibs in front.
Stokes nearly added a killer second for Hibs on 75 minutes when he burst free, but another cracking save from Fox kept County alive.
Staggies sub Alex Schalk was denied by a Laidlaw save with 10 minutes left and Stokes hit the woodwork late on as Hibernian headed south with a result that takes them just behind St Johnstone and Aberdeen ahead of their trip to Lennon’s former club Celtic.