Burglars stole a holdall and safe containing jewellery during a raid at a house on Fall Lane at Liversidge near Dewsbury.
Police said the stolen items had belonged to the victim's mother, who died recently.
Kirklees Police have issued photographs of some of the items stolen in the burglary, which happened between 7.15am and 7.15pm on Wednesday October 28.
Among items taken were a gold cased wristwatch, cluster ring, emerald and diamond ring, claw set ring and a wedding band.
PC Vicky Foley of Kirklees Police burglary team, said "We are appealing for witnesses to this offence and would particularly like to speak to anyone who has been offered this jewellery for sale.
"It belonged to the victim's mother who passed away recently so is obviously of tremendous sentimental value to him.
"Anyone who has information is asked to contact myself at birklees burglary Team three on 101, referencing crime number 13150439660.
"Information can also be passed anonymously to Crimestoppers on 0800 555 111."