The two potential opponents were due to meet for their third round tie on Saturday but their game was postposed due to a frozen pitch at the Gaughan Group Stadium with the game rescheduled for Tuesday 14 January.
The fourth round clash will take place over the weekend between February 7 and 10 with the precise date and kick-off time to be confirmed in due course.
Leyton Orient are currently eighth in League One while Derby are 18th in the Championship.
City kicked off this year’s FA Cup campaign with an 8-0 victory over League Two Salford City at the Etihad.
Among the scorers were James McAtee, who hit a hat-trick, Divin Mubama on his City debut and Nico O’Reilly with his first goal for the Blues.
Jeremy Doku scored twice including the opener, while Jack Grealish was also on target in our first-ever game against the Ammies.
We now face an away clash and keep an eye on mancity.com and the official Manchester City app where we will bring you all the dates and times as soon as they are confirmed.
FA CUP FOURTH ROUND DRAW
Manchester United v Leicester City
Leeds United v Millwall/Dagenham & Redbridge
Brighton v Chelsea
Preston/Charlton v Wycombe
Exeter v Nottingham Forest
Coventry City v Ipswich Town
Blackburn Rovers v Wolves
Mansfield Town/Wigan v Fulham
Birmingham v Newcastle
Plymouth Argyle v Liverpool
Everton v Bournemouth
Aston Villa v Tottenham
Southampton/Swansea v Burnley
Leyton Orient/Derby County v Manchester City
Doncaster Rovers v Crystal Palace
Stoke City v Cardiff City
