Nomura was born in the coastal fishing village of Amino (now Kyōtango) in Kyoto Prefecture. When he was three years old, his father died of disease while serving in China during the Second Sino-Japanese War. Nomura grew up in poverty with his mother and older brother. With the help of his brother, he was able to attend high school.
After graduating from Mineyama High School, Nomura joined the Nankai Hawks after a tryout in 1954. The team's manager at the time believed he'd at least be useful as a catcher for pitching practice. That year, Nomura played in nine games and went hitless for the season. The Hawks discussed cutting him from the team, however, he was given another chance reportedly after Nomura offered to play for free and even threatened to throw himself in front of a train if he was let go.
During a career that spanned four decades from 1954 to 1980, Nomura hit 657 home runs and led the Pacific League in homers eight straight seasons. (However, it should be taken into consideration that his home park, Osaka Stadium, measured only 276 feet down the lines until 1972, and 300 feet from 1972 onward, and 380 feet to straightaway center—tiny dimensions by Major League Baseball standards.) He finished his career with 2901 hits.
In 1965, Nomura won the league's first Triple Crown. He was a player-manager between 1970 and 1977. He played for 26 years, the longest NPB playing career until Kimiyasu Kudo pitched in his 27th season in 2008; Kudo retired in 2010 having played 29 seasons.
Nomura began his 24-year managerial career as player-manager of the Hawks in 1970. During his eight year stint as Hawks manager, he led the team to the Pacific League title in 1973. After his playing career, Nomura went on to become a full-time manager. From 1990 to 1998, he managed the Yakult Swallows, leading them to four league titles and three Japan Series championships. While managing the Swallows, Nomura mentored the team's catcher, Atsuya Furuta. Under Nomura, Furuta flourished and became a hall of fame catcher in his own right.
Following his role as Yakult manager, Nomura joined the Hanshin Tigers and managed the team from 1999 to 2001. The team finished last in the Central League all three seasons. On December 5, 2001, his wife, television personality Sachiyo Nomura, was arrested for tax evasion. Nomura resigned from his managerial position the next day. His wife was accused of hiding ¥45 million of his income, however Nomura was not accused of any criminal responsibility.
After the scandal, Nomura managed the amateur corporate league team Shidax from 2003 to 2005. He left after three seasons to return to NPB. The Tohoku Rakuten Golden Eagles had a poor showing during their inaugural 2005 season. It was the first PL club in 40 years to lose at least 90 games in one season. They finished with a 38-97-1 record. Hoping to improve for their second season, the team hired Nomura to manage the club because of his experience. Over the next four season, he helped turn Rakuten around. By his final season with the team, the Eagles finished the regular season in with their best-ever showing up to that point in time, second place, securing them a position in the Climax Series. After losing in the final stage of the 2009 Pacific League Climax Series, Nomura retired from managing at the age of 74. As a manager, Nomura recorded 1,565 wins, the fifth-most wins of any manager in NPB history.
During his playing time, Pacific League games were rarely televised. Because of this, Nomura was often overshadowed by his Central League contemporaries such as superstars Sadaharu Oh and Shigeo Nagashima of the Yomiuri Giants. He openly resented this and felt he never received the attention that he deserved as a player. Over 26-season playing career, however, Nomura amassed a number of awards, titles and records. During his time with the Hawks, he won five Pacific League MVP Awards – the most of any PL player and second-most all-time. Nomura also led the PL in home runs for nine seasons, eight of which were consecutive and won 19 Best Nine Awards for best catcher in the league. He accumulated 657 home runs, 1,988 RBIs and 2,901 hits in 3,017 games, all of which are 2nd in the all-time rankings. He was elected into the Japanese Baseball Hall of Fame by the Selection Committee for Players in 1989.