The Orange equaled the best start to a season in school history, having won their first 20 games of the campaign. The 2011-12 Syracuse team also went 20-0.
Syracuse had a three-point lead at halftime and then relied on Ennis to pull off the road win. C.J. Fair added 16 points and eight rebounds while Jerami Grant had 10 points.
The Orange improved to 7-0 in the Atlantic Coast Conference with Virginia a half game behind.
Syracuse shot a modest 36 percent and hit only 3-of-14 from 3-point range, but the Orange held a 51-28 advantage on the backboards. Syracuse had 17 offensive boards to just five for the Demon Deacons.
Wake Forest (14-7, 4-4) was led by 12 points each from Travis McKie and Devin Thomas. The Deacons had won their previous 13 home games.