Markkanen, a native of Finland, committed during his official visit to Arizona.
"I think I have a chance to go play against great guys every day in practice," Markkanen said. "I think I can get minutes here. I like everything I see here."
Prior to visiting Arizona, Markkanen visited Utah and North Carolina. Both of those official visits were within the last week.
"They showed me everything that they have here and I liked it," Markkanen said about Arizona.
"I'm glad I have a chance to commit now and relax," he added. "All three schools are great and I knew it was going to be hard, but I think I made the right choice."
Markkanen is Arizona's first pledge of the 2016 recruiting class.
Markken starred in international competition this past summer, as he averaged 18.2 points and 6.3 rebound for Finland’s U18 team in the FIBA U18 European Championships.
While Scout doesn’t rank prospects that reside overseas, Markkanen, a 6-foot-10 power forward, is equivalent to a five-star prospect. At his size, he’s mobile, has great hands and touch and stretches the floor with his jump shot.