Gale-force winds blowing in the area had been hampering firefighting efforts since the fire broke out on Monday, but no inhabited areas were in immediate danger.
Skopelos Mayor Christos Vasiloudis said that the fire was brought under partial control, and that he hoped it would be fully under control in a few hours' time.
It was not clear how the blaze began. It continued to burn through the night despite overnight rainfall.
Greece often suffers from extensive forest fires, but they usually occur during the summer months.
Last August, devastating fires raged out of control across the country for a week, killing more than 60 people.
