Tai Kai-yin was executed on Shek O beach by the Japanese 52 years ago.
But unlike other war heroes he has never been honoured with a grave at Stanley Military Cemetery.
Now his son, Tai Kwok-yuen, 57, is lobbying Britain to erect a headstone to his father and other men who sacrificed their lives working for the British Army Aid Group.
Around 44 agents of the BAAG, which spied on the Japanese and helped get food and medical supplies to prisoners of war, are buried in Stanley.
But Tai, who was executed on October 31, 1944, shares a grave with four others in Diamond Hill.
His son, president of the Church of the Latter Day Saints in Hong Kong, is now campaigning to get a proper BAAG headstone erected.
'These poor soldiers should be honoured. Others executed on the same day have memorial stones. I think these heroes should too,' he said. 'They have not been suitably recognised for their unusual courage and loyalty to Hong Kong and the United Kingdom.' Veteran campaigner Jack Edwards, of the Royal British Legion, traced confirmation of Tai's service and execution through police and war records.