A 76-YEAR-OLD man has been charged over an alleged sexual assault at a Melbourne shopping centre.

A 28-year-old mother, who cannot be identified, says she was approached by an unknown man on the night of January 27 at Ringwood's Centro Shopping Centre as she walked past a liquor store.

He told her she looked cold and needed a hug before wrapping his arms around her.

Police say the man then sexually assaulted the woman before walking away.

Knox detectives on Saturday night charged the man with rape and indecent assault.

He was bailed to appear at the Melbourne Magistrates Court on February 8.