It was the fourth time a player from Iran has won the award since it was introduced by the Asian Football Confederation (AFC) in 1994.
"This award is the result of years of hard work," Karimi said on Wednesday. "I want to dedicate this to the people of Iran."
The 26-year-old, who plays for United Arab Emirates club Al Ahli, helped Iran finish third at this year's Asian Cup and was the tournament's joint top scorer with five goals.
Karimi has attracted interest from several European clubs and said he was anxious to make his mark overseas after scoring 27 goals for Al Ahli this year.
"If I keep
Previous Iranian winners of the AFC award were Khodadad Azizi in 1996, Ali Daei in 1999 and Mehdi Mahdavikia, who won last year. All three played in the German Bundesliga.
Adnan Hamd was named coach of the year after guiding war-weary Iraq to the Asian Cup quarter-finals as well as the last four of the Athens Olympics.
Japan were honoured as the continent's top national team after retaining the Asian Cup. Saudi Arabia's Al Ittihad were named as the top club team after capturing the Asian Champions League title earlier this month.
Japan's Homare Sawa was named the top women's player of the year.