A mum and her young child have been terrorised by four men who broke in and ransacked their home in Sydney’s west.

The 31-year-old woman was awoken just after 2.30am by noises coming from the loungeroom of her Guildford unit.

Her four-year-old son and a couple in another room remained asleep as she went to investigate.

She was confronted by a man armed with a knife, who threatened her and demanded cash.

Another three men were also there, ransacking the place.

The armed man tried to force his way into the unit’s second bedroom but the couple, aged 32 and 28, had barricaded the door.

The men made off with a TV before police arrived and are still on the run.

The man armed with the knife is described as Caucasian, in his late 20’s, between 170 and 180cm tall and wearing a grey hoodie.

A second man was carrying a black bum-bag over his shoulder while the two couldn’t be described.

Anyone with information is urged to call Crime Stoppers in 1800 333 000