One member of the gang knocked on the door of the house on Spaines Road, Fartown, Huddersfield, asking if the occupant had ordered any food.
Five other people then piled into the property holding weapons and demanding money.
The victim, a man in his 30s, was attacked before the gang made off with a large amount of cash as well as a mobile phone, jewellery and credit cards.
The incident happened between 11pm and midnight on Wednesday.
One of the suspects is described as a white man, aged around 35 and skinny with black hair and stubble.
He was wearing a short black jacket with a T-shirt underneath.
Three of his accomplices are described as tall and slim Afro-Caribbean men.
Det Con Andy Clayton, of Huddersfield CID, said the victim had suffered a “terrifying” ordeal.
He went on: “I would like to appeal to members of the public to come forward with any information if you saw anything suspicious in the area on this night or recognise the descriptions of the suspects.”
Anyone with information is asked to ring Huddersfield CID using West Yorkshire Police’s 101 phone number or the independent charity Crimestoppers on 0800 555111.