[1] Imamiya attended Meiho High School, pitcher-shortstop, hitting 62 home runs and throwing as hard as 154 km/h(96 mph).

On November 26, Imamiya was honored for the Mitsui Golden Glove Award at the 2013 Professional Baseball Convention.

[21] On January 26, 2017, Imamiya declined to participate in the 2017 World Baseball Classic due to rehabilitation of his right elbow.

[23] On June 26, Imamiya was selected by fan voting for MyNavi All-Star Game 2017, and has participated for the fourth time in a row since 2014.

[24] He finished the regular season in 141 games with a batting average of .264, a 14 home runs, a RBI of 64, a 15 stolen bases, and a 52 sacrifice bunts.

And he recorded .266 batting average, 11 home runs, 45 RBIs, 5 stolen bases and 22 sacrifice bunts.

[33] In the match against Chiba Lotte Marines on August 8, Imamiya hit a reversal home run with a pinch hitter for the first time.

[34] He finished the regular season in 106 games with a batting average of .256, a 14 home runs, a RBI of 41, a 4 stolen bases, and a 7 sacrifice bunts.

In the 2019 Pacific League Climax Series against the Saitama Seibu Lions, Imamiya won the Pacific League Climax Series Most valuable player Award with 5 hits and 6 RBIs including 3 home runs in Game 4.

[36] In the match against the Hokkaido Nippon-Ham Fighters on July 3, 2020, Imamiya achieved the youngest 300 sacrifice bunts in NPB history.

On April 8, 2021, Imamiya set a Pacific League record with a total of 306 sacrifice bunts.

[40] Early in the 2021 season, he played 125 games with rest while both calves were not in perfect condition, but his batting average was his worst at .214.

[45] He finished the regular season with a .296 batting average, fourth in the league, as well as seven home runs and 47 RBI in 130 games.

[46] On April 12, 2023, Imamiya hit 350 sacrifice bants the fourth players in the NPB history ,and the youngest record.