Several teams have been chasing Asano, who has five caps after making his international debut in August last year and is expected to be a part of the Japan squad for the Rio Olympics.
"Takuma is a talented young striker and very much one for the future. He has had an impressive start to his career in Japan and we look forward to him developing over the next couple of years," Arsenal manager Arsene Wenger told www.arsenal.com.
Takuma joined Sanfrecce as an 18-year-old at the start of 2013 and scored 11 goals in 56 appearances. He won the J1 League in 2013 and 2015, the Japanese Super Cup in 2013, 2014 and 2015, and was voted J-League 'Rookie of the Year' in 2015.
