Hiroyama was born in Sodegaura on May 6, 1977. After graduating from Narashino High School, he joined his local club JEF United Ichihara in 1996. He became a regular player from first season. The club won the 2nd place in the 1998 J.League Cup. In 2001, he moved to Paraguayan club Cerro Porteño. From 2002, he played for Sport Recife, Braga and Montpellier. In summer 2004, he returned to Japan and joined Tokyo Verdy. In 2005, he moved to Cerezo Osaka on loan and returned to Verdy in a year. Toward the end of his career, he played for Thespa Kusatsu (2009–2010) and Richmond Kickers (2011–2012). He retired end of 2012 season.