On the day he won his 100th Test cap, Clarke was named the ICC's Test Cricketer of the Year and overall winner of the Garfield Sobers Trophy for the overall outstanding performer in the voting period.
From August 7, 2012 to August 25, 2013, Clarke was the world's leading run-scorer with 1559 runs at 70.86, including five centuries - two of which were doubles.
"I was very surprised, to be honest, I think probably because there are so many guys who are playing so well around the world at the moment," Clarke said as the award was announced.
"I definitely didn't expect to have won this award but it is a prestigious award and an honour, and something I'm certainly proud of."
Clarke's efforts with the bat were all the more amazing, given they came during a 4-0 defeat in India and a 3-0 Ashes loss in England.
"I'd swap it for the team to have success, that's for sure," Clarke said.
"I think there's a lot of areas of my game that can improve, and I work on those daily.
"If I want to become a great player, I need to make sure I'm scoring runs and helping this team win games for a few more years to come yet."
The Australian skipper had already been named in the ICC Test and ODI Teams of the Year.
Clarke was joined on the winners' list by Sri Lanka's Kumar Sangakkara, who was named ICC ODI Cricketer of the Year, and India's Cheteshwar Pujara, named as ICC Emerging Cricketer of the Year.