Cowes RNLI Lifeboat was paged for an immediate launch at 2.08pm on Tuesday (August 28).
The RNLI crew assisted a man in the water at Lepe Beach on the mainland, who had entered the water to rescue his blind dog, which was in difficulties.
Southampton and Lymington Coastguards were also in attendance on shore.
Upon arrival, the man was being brought ashore, but the dog was clearly in difficulties.
The lifeboat was brought nearby the animal and Lifeboat Helm, Mark Harker swam to its aid and brought it onto the lifeboat to be taken ashore.
A spokesman for Cowes RNLI Lifeboat said: “The dog, which was completely blind was in grave difficulties and the lifeboat arrived just in time.
“The dog’s owner, now safely ashore and with Southampton Coastguard, was awaiting an ambulance to be checked over after his ordeal.
“As the Coastguard helicopter was also overhead and the ambulance had not yet arrived, Cowes Lifeboat set out from the beach to line transfer the helicopter’s paramedic to assist the casualty.
“The ambulance subsequently arrived and the man was declared well by the medical staff. The dog was also happy to be reunited with its owner.
“Upon transfer of the helicopter paramedic back to his aircraft, the lifeboat was stood down and returned to station at 3.10pm.”
Video Credit: Jane Halliday