And it may soon be returned to its owner more than 3,000 miles away on the other side of the Pacific Ocean.
David Baxter, a technician at the radar station on Middleton Island in the Gulf of Alaska, came across the ball as he was beach combing.
The ball had Japanese characters written on it, from which Baxter's wife was able to translate the name of a school that was in the area hit by the tsunami, according to a blog post by the National Oceanic and Atmospheric Administration.
An enormous amount of debris was swept into the Pacific by the tsunami that hit northeast Japan on March 11, 2011, killing thousands of people.
A number of objects, both large and small, have so far made their way as far as the coast of North America, including a rusty fishing trawler that the U.S. Coast Guard sank earlier this month. But the ball "may be the first identifiable item that could be returned," according to the NOAA.
Misaki Murakami, a 16-year-old high school student, says he has "no doubt" that the ball is his after hearing that his name was among the characters written on it, Japan's Kyodo news agency reported Sunday.
Murakami, who is from the severely tsunami-damaged city of Rikuzentakata, said he was surprised but thankful to Baxter for finding the ball, according to Kyodo.
He can be grateful for Baxter's interest in beach combing, a popular pastime on Middleton, according to the NOAA, which describes the 4.5-mile-long island as "treeless and windswept."
The agency, which has been monitoring tsunami debris, said it was working with the U.S. State Department, the Japanese Embassy, and the Japanese consulate in Seattle to establish a process to return items that may be found in the future.
Not all objects will find their way home, though. A volleyball found on the U.S. side of the ocean "doesn't have enough information" on it to trace its owner, the NOAA said.