Born in Rikuzentakata, Iwate Prefecture, he enrolled in Hosei University but withdrew when he successfully auditioned for a part in Kamen Rider. He made his debut as Hiroshi Tsukuba in Skyrider.

Hiroaki appeared in a lot of jidaigeki television dramas. He appeared the NHK jidaigeki On'yado Kawasemi in 1980–81, and in a new series Shin On'yado Kawasemi in 1997. He appeared in Hissatsu series Hissatsu Shigotonin V as the florist-turned-blacksmith named Masa, and as a repeating character in Series and popularity.

Five Taiga drama roles are among his credits. They are in Haru no Hatō (1985), Kōsaka Masanobu in Takeda Shingen (1988), Fujiwara no Kiyohira in Homura Tatsu (1993), Akechi Mitsuhide in Hideyoshi (1996), and Yanagisawa Yoshiyasu in Genroku Ryōran (1999). In the annual TV Tokyo New Year's spectacular, he portrayed Sasaki Kojirō in Miyamoto Musashi (1990), Kira no Nikichi in Jirōchō Sangokushi (1991), Yagyū Jūbei in Tokugawa Bugeichō Yagyū Sandai no Ken (1993), and Araki Mataemon in Tenka Sōran Tokugawa Sandai no Inbō (2006). Among the jidaigeki series he has starred in are Hatchōbori no Shichinin (2000-06), Zenigata Heiji (2004-05), Yagyū Jūbei Nanaban Shōbu (2005–07), and Shikaku Ukeoinin (2007). Additionally, he portrayed Oda Nobunaga in Taikōki Tenka o Neratta Otoko: Hideyoshi" (2006).

He has appeared in more than fifteen films, including several in the Kamen Rider and " franchises. Further films to his credit include Gokudō no Onnatachi 2", Juliet Game" and Iron Maze" (In a Grove).