The video shows a diver hacking into the large pink net, which is wrapped tightly around the whale’s tail and down its body to its head.
The Coast Guard said the whale was restless, making it difficult to release as they could not work continuously.
Boaters sounded the alarm after spotting it in trouble near the Aeolian Islands archipelago in southwest Italy on Saturday.
Another sperm whale was released from a fishing net in the same area three weeks ago, the coast guard said.
More than 100 km (62 miles) of fishing nets have been seized since the start of the year as Italian authorities try to fight illegal fishing.