Two men wearing ski masks forced their way into a house in Mile Oak and demanded money.
Sussex Police said that the aggravated burglary happened late on Thursday night (29 May).
The force said: “Around 11pm two suspects knocked on the door of a property in Mile Oak Road.
“One of the occupants of the house, a 20-year-old man, answered the door and two men wearing ski masks pushed their way in and demanded money.
“On hearing voices, the owner of the property came downstairs and the two suspects said, ‘wrong house’ and left in the direction of Old Shoreham Road.”
Detective Constable Mandy Dunk said: “Although the suspects didn’t take anything or threaten anyone, this was a very traumatic experience for the family involved.
“Both suspects are described as wearing dark clothing with dark ski masks and gloves. One was of a large build, around 5ft 11in, and the other was skinny and around 5ft 7in.
“We are appealing to anyone who has information about this incident or witnessed these two men leaving the area to please get in touch.”
Anyone with information is asked to phone Sussex Police on 101, email 101@sussex.pnn.police.uk or contact the independent charity Crimestoppers anonymously on 0800 555111.