Kobayashi was born in Machida on September 23, 1987. When he played for Takushoku University, he also played for J2 League club Mito HollyHock in 2008. After graduating from the university, he joined J1 League club Kawasaki Frontale in 2010. He became a regular player from 2011. In 2017, Kawasaki won the J1 champions first time in the club history. He also became a top scorer with 23 goals and was selected MVP award. Kawasaki won the J1 champions in 2018 and 2020.
On October 10, 2014, Kobayashi debuted for the Japan national team against Jamaica. He played 14 games and scored 2 goals for Japan until 2018.