The 62,000-ton vessel floated free a mile off Sidmouth after 58,000 tons of water was pumped from her holds.
The ship has been towed 500m south of its original position where it will be inspected by divers for several days before its next move.
The vessel carrying 2,300 containers was damaged in a storm in January.
A barge with winches and cranes, along with tugs and an anti-pollution vessel are assisting at sea in Branscombe Bay.
The Maritime and Coastguard Agency (MCA) said the decision to refloat the vessel had been made to prevent further deterioration in the structure of the ship and to prevent further damage to the environment.
About 1,900 seabirds along the coast were affected after 200 tonnes of oil leaked from the vessel soon after grounding
Spokesman Fred Caygill told BBC News: "It's a fantastic milestone, everyone here is very relieved.
Looting spree
"After looking at the ship from the same angle over the past six months it's amazing to see it floating free."
Since the decision was made in January to beach the vessel, salvors have worked around the clock to remove all of the containers from the stricken ship.
Approximately 150 of them were classed as having potentially hazardous contents.
More than 100 containers went overboard and 58 were washed ashore, leading to a scavenging and looting spree.
Of the containers that went overboard, one contained battery acid and perfumes, and one small gas bottles for car airbags.
Others housed a variety of goods including BMW motorbikes and car parts.
HOW THE MSC NAPOLI WAS REFLOATED
^ Back to top | BBC Sport Home | BBC Homepage | Contact us | Help | ©
~RS~q~RS~~RS~z~RS~51~RS~)