Soejima was born inSaga on July 26, 1959. After graduating from high school, he joinedYanmar Diesel in 1978. After reserve team in 2 season, he was promoted top team in 1980. In 1980, the club won the champions inJapan Soccer League and he was selected Best Eleven. The club also won1983 and1984 Emperor's Cup. In 1991, he moved to Division 2 clubSumitomo Metal and played in 1 season. He retired in 1992.
After retirement, Soejima started coaching career atKashima Antlers (formerSumitomo Metal) in 1992. He moved toGamba Osaka in 1996. In 1998, he returned toCerezo Osaka (formerYanmar Diesel) and became a manager in 2000. He was sacked in August 2001. He managed his local clubSagan Tosu in 2002 andVissel Kobe in 2003. In 2005, he returned to Cerezo Osaka and managed youth team until 2008. He moved toKataller Toyama and became a coach. In 2010, he moved toThespa Kusatsu and managed until 2012. In 2015, he moved to Thailand and became a managerAyutthaya.
