The mask, which depicts the supernatural bird Huxhukw, and is one of three bird masks used by the Kwakwaka'wakw peoples during winter ceremonies.
It was discovered missing from a shed in Alert Bay on Cormorant Island, off northern Vancouver Island, last Friday.
Police believed the thief would try to sell the striking mask, which has a five-foot-long beak, and is painted in bright colours, it to a gallery or an art collector.
Police said today that a private collector surrendered the mask to the Alert Bay RCMP detachment on Wednesday.
"Due to the circumstances, they will not be facing any charges of possession of property obtained by crime," police said in a press release.
Police did track down a suspect, who was arrested and released without charges but with a promise to appear in court in Port Hardy on Nov. 12.
Police are recommending charges of breaking and entering, theft and public mischief.
Use of aboriginal masks was banned in Canada from the late 1800s until 1951, and during that time many masks were seized. While some were returned to First Nations, others are now held in public and private collections.