"A member of the public called in with information about the sculpture which was then recovered along with a bronze plinth which had also been taken from the Henry Moore Foundation," she said.
Lesley Wake, chief operating officer of the foundation, said she was "thrilled" the sculpture had been recovered.
Sundial was the latest work by the abstract artist, who died in 1986 aged 88, to be targeted by thieves.
The foundation, which is based at Moore's former home, suffered an unresolved theft in 2005, when the two-ton Reclining Figure - insured for £3 million - was loaded onto the back of a lorry by three men.
It has never been recovered and a reward of £100,000 for information is still outstanding.
In 2010, a Moore painting, Three Reclining Figures On Pedestals, was one of three works of art worth a combined £230,000 stolen from a gallery in Worcestershire.
In February a Moore abstract nude sold for £19.1 million, which auctioneers Christie's said was a record for the artist.