The young Foxes went into the clash on the back of three consecutive victories in U18 Premier League South, but the visitors were the league's leaders ahead of kick-off at LCFC Training Ground.
It was City who went close first as Cottagers goalkeeper Alfie McNally saved Kian Pennant's low drive at goal. Joe Wormleighton then fired over for the in-form hosts in Seagrave. Leicester shot-stopper Arlo Doherty, on the other hand, had to be alert to Michael Olakigbe's strike from a tight angle.
Olly Sanderson’s long-range effort was kept out by Doherty early on in the second half, before Henry Cartwright’s low ball into the box was eventually cleared by Fulham's defensive ranks. Olakigbe also hit Thomas Wilson-Brown's cross straight at Doherty for the west Londoners.
Shortly after Pennant struck over the bar, the young Foxes forward located Butterfill, whose powerful drive beat McNally and secured all three points for Leicester's youngsters. It means City sit atop of the league after eight games, with six wins and 18 points to their name.
Next up, the Club's Under-18s head to West Bromwich Albion in the Premier League Cup on Saturday (1:30pm kick-off), before entertaining bottom of the league Norwich City in U18 Premier League South on Saturday 20 November (12:30pm kick-off).
The details...
City: Doherty; Grist, Wilson-Brown, Godsmark-Ford; Dawkins, Lindsay, Cartwright, Cover (Butterfill 70'), Wormleighton (c); Popov, K. Pennant.
Subs not used: Chibueze, Lewis, Read, Kutshienza.
Goal: Butterfill 87'.
All times GMT.