He then participated in Japan Formula 4 in 2002 where he won two victories in a year and obtained Second Series as well as MVP.

Fujii received a scholarship and participated in Formula Dream by HONDA for two years from 2003.

Fujii made his debut in Super GT, which is the top category in Japan, in 2005.

Once he started to race with a Nissan 350Z, he reached the podium four times and won the 4th position in 2006.

He then received a contract with NISMO as a factory driver in 2008, although he continued to race with a Nissan 350Z in Super GT till 2008.

From 2010 to 2013, he contracted with Hankook Tire as a factory driver and raced with a Porsche GT3R (RSR) during that 4 years.