A display of the work of Philip Naviasky, who lived on Scott Hall Road, Leeds, until the early 1980s and was possibly of Polish descent, is on show in a Leeds shop.
Many of his portraits, mostly anonymous, are thought to be of West Yorkshire people.
And now the search is on to match up faces to the paintings in charcoal and colour.
Naviasky, a popular character, died aged 90 in 1983.
People used to queue up outside his studio at his home in Scott Hall Road, to be painted in return for a small payment.
Now his pictures can sell for thousands of pounds each and he is fast becoming a collectable modern British artist. He would single out interesting faces while out and about and invite people up to his studio.
Naviasky was often found frequenting buses, queues and shopping areas of Leeds to find interesting people to paint.
Now a Leeds gallery, located inside the Rug Collection Shop in Chapel Allerton, has launched an appeal to find the featured faces.
Shop owner Tony Frais said: "Naviasky was a real character and his work is causing a lot of interest.
"We have had lots of people interested to find whether he painted their parents or grandparents.
"We want to find some of the anonymous faces he painted."
As well as portraits much as his work was done in the South of France, Spain and Portugal.
He also painted a gipsy camp on the Yorkshire Moors and many prominent people in the early part of the 20th century, including Lord Nuffield, Lord Brotherton, Lord Austin and Ramsay MacDonald.
The exhibition called Did He Paint Your Mum? is on show at the shop until the end of next week at 45, Harrogate Road, Chapel Allerton.
It will be open on Sunday. Telephone 0113 237-4845.

alison.bellamy@ypn.co.uk