A man has been attacked by three youths as he stood in a west Sydney street waiting for his dinner.

Police say the 42-year-old was outside a takeaway food restaurant on Everton Road, Strathfield early on Tuesday evening, when he was attacked by three teenagers.

The youths escaped and the victim ended up in hospital with head wounds that required 22 stitches.

He has told investigators he saw three males aged in their late teens walking towards him from Strathfield Railway Station at about 6.30pm (AEDT).

One was waving a stick in the air and allegedly spat in the man's face as they walked past.

It is believed he hit the man with the stick as another punched him in the head.

All three youths surrounded the man before the third youth attacked him with what appeared to be a shopping trolley handle.

The 42-year-old grabbed the youth armed with the handle but he escaped and the trio ran off towards Wentworth Road.

Police have established a crime scene and have appealed for witnesses to come forward.

Anyone with information can contact Burwood Police or Crime Stoppers on 1800 333 000.