The incident – which happened at around 4.25pm on Sunday, May 23 – left the 86-year-old shaken, but thankfully uninjured.
He was at his home on Waukglen Drive, Darnley, when the three men forced their way in and proceeded to threaten him before leaving with several items, including some jewellery.
All three suspects have been described as white and aged roughly between 20 and 30.
One man was wearing a light blue shirt with cream-coloured trousers, the second was in a white hooded top and dark trousers and the third was dressed fully in dark clothing.
They drove off in a white car after leaving the elderly man’s home.
Detective Constable Kris Elliott said: “Targeting an 86 year-old man and making him feel vulnerable in his own home is despicable.
“Our enquiries are continuing to identify and trace the three men involved and anyone with any information that will assist our investigation should contact the Community Investigation Unit at Govan through 101 quoting reference 2532 of May 32.”
If you would like to report information on this crime anonymously, you can contact Crimestoppers on 0800 555 111.