Scott C Waring, a YouTuber and extraterrestrial investigator, shared the picture of what he alleges is an ancient alien ship frozen into an iceberg off the east coast of the island.
He claimed the alien craft had been revealed by the melting ice sheets.
According to the Waring, Google Earth shows the triangular-shaped object is around 68m wide.
Writing on his website ufosightingsdaily.com, Scott wrote: "I found a triangle UFO that was attached to an iceberg floating off of Greenland today.
"I used Google Earth maps to find it. The ruler on the map states that the UFO is 68 metres across.
"It's possible this UFO crashed to Earth millions of years ago and got buried beneath a glacier that melted little by little, dropping fragments of itself into the ocean."
He went on: "The black line across the cockpit area is very obvious and shows us that this really is a craft, not a coincidence.
"The corners of the craft are perfectly equal and slightly rounded off.
"This triangle craft looks like there was ice above it, but apparently it melted off and only the side areas of ice remain still attached to it."
Scott, who also runs the YouTube channel ET DATABASE, claimed to have made the find on Sunday, September 13.
Comments on his video, posted yesterday, were mixed, with one YouTuber viewer writing: Amazing! Someone needs to check it out!"
However, another commenter wrote: "I believe in aliens but this is such a reach, the government wouldn't let something like that be noticed, plus people that live there could find it very easily."
In the past, he has made a series of outlandish claims about potential objects which he believes are alien crafts or technology.
Last week, Scott shared a video showing a "UFO changing shape" as it hovered in the night sky.
The video, filmed in Calgary, Canada, shows an orange object with a white light appearing to fly close to it.
Although Scott was convinced the short clip showed "two UFOs" in the sky, other viewers pointed it it may just have been a flare.