The crayon, pen and ink sketch by the Castleford-born sculptor, titled Three Reclining Figures on Pedestals, was one of three pictures, together worth 155,000, snatched during a break-in at Trinity House gallery at High Street, Broadway in Worcestershire.
Now, loss adjusters have re-issued a call for information about the artworks.
Simon Shore, co-owner of Trinity House, said: “If there is an attempt to sell them on, these instantly recognisable pictures by well-known British artists will be worthless on the open market.”
A 40,000 oil painting,Thames Barges At Low Water, Pin Mill, by Edward Seago and a 70,000 oil painting, In The Lily Garden, by Dorothea Sharp were the other pictures taken in the raid.
The burglary happened at 1.50am on August 6. Four young men in dark clothing and hats were later seen running off.
Henry Moore, son of Yorkshire miner Raymond Moore, was born at Roundhill Road, Castleford, on July 30,1898.
He trained at Leeds School of Art and went on from there to become the UK’s greatest sculptor.
His work now sometimes sells for millions of pounds at auctions.
When Henry Moore died 24 years ago next Tuesday he left more than 1m in his will.
The loss adjusters can be contacted on 01483 89199 or information can be passed anonymously to Crimestoppers on 0800 555 111.