Police officers doing their rounds were the last people to see Murwillumbah man Denis Ross, who has been missing since Friday (March 7).
The 73-year-old was spotted by them walking along the Tweed Valley Way near Stotts Island.
Police say they spoke briefly to Mr Ross, who told them he was going to Tweed Heads.
He has not been seen or heard from since that time.
Mr Ross’s family are concerned for his wellbeing due to his age and medical history.
He is described as being of Caucasian appearance, 175cm tall, with grey hair and blue eyes. When he was last seen Mr Ross was wearing a blue collared shirt and pants.
Police are urging anyone with information about this incident to call Crime Stoppers on 1800 333 000 or use the Crime Stoppers online reporting page: https://www1.police.nsw.gov.au/.