City actually went a goal down in the opening stages when Brooke Chaplen scored for Reading early on. But a first half-hat-trick from England star Nikita Parris plus a goal soon after the interval from Demi Stokes put the Sky Blues 4-1 up and on course for an easy win.
FULL-TIME | A close one in the end, but we managed to hold off the Royals to come out on top! — Man City Women (@ManCityWomen) March 13, 2019
A first-half hat-trick from @lilkeets plus a @DemiStokes strike sees us secure the three points at Adams Park.
⚪ 3-4 #mancity pic.twitter.com/X6G0SUZkfO
A penalty from veteran Fara Williams on the hour mark reduced the deficit, with Kirsty Pearce then setting up a nervous final moments after pulling another back for Reading late on.
Unbeaten City held on and take their WSL record for the season to 12 wins and five draws.
Arsenal will have a chance to eat into that five point lead when they host Bristol City on Thursday night in one of their three games in hand.
The potentially huge clash between Arsenal and City on the final day of the season on 12 May could yet decide which club is crowned 2018/19 WSL champions.
Elsewhere on Wednesday, reigning champions Chelsea thrashed Liverpool 4-0 away from home to keep in touch with the leaders.
A hat-trick from the returning Fran Kirby, who featured prominently in the launch of England's new bespoke World Cup kits this week, was the main difference for Chelsea, with Adelina Engman scoring a fourth deep into stoppage time.
Third place Chelsea moved one point behind Arsenal as a result of the win, having played three games more, and are six points adrift of leaders City. With only three more games left for them to play it is almost certainly too late for Chelsea.
Liverpool, meanwhile, remain eighth after a difficult and disappointing season.
Also on Wednesday, bottom club Yeovil earned a rare point by holding Brighton to a 1-1 draw. Ellie Mason's equaliser for Yeovil cancelled out Victoria Williams' opener for the Seagulls.
But that result did not close the gap on second bottom Everton, who actually won their game against West Ham to put five points between themselves and relegation to the Women's Championship. A very late Hannah Cain goal was enough for the Toffees to claim the 1-0 victory.