Makihara was born on 18 May 1969 in Takatsuki, Osaka, Japan. He attended Aoyama Gakuin University to study English literature. In addition to creating songs for his own music career, he has written, produced and performed songs for many other artists, the most notable being SMAP's Sekai ni Hitotsu Dake no Hana. He is ranked at No.84, in a list of Japan's top 100 musicians, provided by HMV. He was also invited to write the song "The Gift" for English band blue in their album "Guilty".
Makihara made his debut to the J-Pop scene in the early '90s after performing on a televised song competition program. He made a name for himself with the release of songs such as "Mou Koi Nante Shinai" (もう恋なんてしない) and "Donna Toki mo." (どんなときも), both of which, among several others, are covered to this day by current popular artists (including English-language covers by various American artists). Some of his music has been translated into other languages, and "Donna Toki mo", specifically has been remixed by Bemani artists "Dream Line Out" for use on Konami's Beatmania game series.
Much of his music's lyrical content has revolved around the subject of romantic love, though themes of profound joy, reminiscence, gratitude and deeper spiritual aspects of the human condition have become predominant in recent years.
In 1999, he was given a suspended 18-months prison sentence for possession of amphetamines.
In 2003 he became famous for composing " Sekai ni Hitotsu Dake no Hana"" (世界に一つだけの花, "The One and Only Flower in the World") which was recorded by Japanese boy band SMAP and sold double millions.
On 13 February 2020, Makihara was arrested for alleged illegal stimulant possession, as police found 0.083 gram of stimulant at his condominium in Tokyo's Minato Ward in April 2018. On 2 August 2020, Makihara was sentenced to 2 years in prison, suspended for 3 years by the Tokyo District Court.