The O's will face Aston Villa in the Capital One Cup - the first time the sides have met since 1975
The last time the two clubs faced each other was back in old Division Two when the O's grabbed a 1-0 lead that day thanks to single goal from Ricky Heppolette.
In the previous 12 meetings between the two sides, Villa have won six, with four draws and just two Orient wins.
The other O's victory is regarded as one of the finest performances in the history of the Club, back in February 1973 when the O's trounced Villa 4-0 with a sparkling performance thanks to goals from Gerry Queen, Paul Harris and two from Barrie Fairbrother.
The two teams also met during Orient's only ever season in the top flight: 1962-63. The Midlands club were winners on both occasions that year with a 2-0 scoreline at Brisbane Road after a 1-0 result at Villa Park.
Villa boss Paul Lambert is no stranger to being on the receiving end of Orient cup upsets as his Norwich side was defeated by the O's in January 2011 when a Jimmy Smith header gave the travelling O's a 1-0 win.
The game will take place during the week beginning August 25 with full fixture and ticket details to follow.