In 1998, by playing the bullied and abused child Noboru Yoshikawa in the drama Great Teacher Onizuka, he started to be recognized by the public. His acting in that drama attracted the attention, and brought him bigger roles. In 2000, he played a deaf person in Summer Snow. In 2002, he starred in the popular drama Gokusen, in which he played a part of a bully, rather than the bullied, as he did in Great Teacher Onizuka. Oguri rose to prominence after his breakthrough role in 2005, as 'Hanazawa Rui' in the popular drama Hana Yori Dango. In 2007, he starred in the drama Hanazakari no Kimitachi e as 'Izumi Sano', co-starring with Toma Ikuta and Maki Horikita. In 2008, Oguri took up another lead drama role in Binbō Danshi by playing an optimistic poor college student named 'Kazumi Koyama'. In 2009, he appeared as lead in the drama Tokyo Dogs as American detective 'So Takakura'. He reunited with Hana Yori Dango co-star Mao Inoue for the drama Jūi Dolittle (獣医ドリトル, Veterinarian Dolittle), which began airing in October 2010. In 2012, he costarred with Satomi Ishihara in Fuji TV's Rich man, poor woman as a young wealthy man 'Toru Hyuga', which earned him the first Best Actor award in 74th Drama Academy Award. In 2015, he reunited with Toma Ikuta after seven years in the TBS drama Ouroboros as 'Tatsuya Danno'.