The Sussex Police rural crime team, with the RSPCA and Trading Standards, carried out a number of raids while looking for a stolen dog, after a tip-off from a member of the public.
They came across Cassie the cocker spaniel, with some puppies who are thought to be hers.
The moment she returned home was captured on camera.
The family said: “We are so thankful to have our Cassie back home, after eight years since being separated from her. Cassie has settled in very well and is enjoying her daily dog walks.”
“As for the three puppies, they have all gone to good homes and are loving their new set family life.
“We want this to bring hope to others who have had their dog lost or stolen. Finally, we would like to thank the police and everyone involved in helping us retain Cassie and her puppies back to us,” they added.
The RSPCA said the owners were “absolutely thrilled” to have Cassie back.
“We assisted police officers as they executed warrants following information related to a stolen dog and were pleased to recover Cassie, and three puppies, and return her to her owners, who were absolutely thrilled to have her home after so many years.”
Sussex Police rural crime team inspector Oliver Fisher said: “As is often the case, it was useful information from the public that assisted us and we are grateful to them as ever for coming forward.
“Dogs can go missing on occasion, but it is extremely rare for dogs to be stolen. I would like to reassure the many thousands of dog owners in the county that with simple precautions, you need not fear this crime.
“I would encourage all dog owners to microchip their dogs, keep an up-to-date photo of the dog, and in the event that it goes missing, inform the microchip company and supply the police with a photo.”