Pyo Ji-hoon debuted with the South Korean boy group Block B in 2011 with the song Freeze! However, the Commission of Youth Protection banned the song, as they deemed it was inappropriate for minors. In June 2011, the group released their first mini album New Kids on the Block. In October 2012, they dropped their debut studio album Blockbuster, which reached number 10 on the Billboard World Albums Chart. In March 2013, P.O. released his first mixtape titled Bigboi Is Ready 2 Showtime. That same year, Block B came back with the extended play called Very Good under a new management.

Pyo Ji-hoon made his theatrical debut in the play Superman Dot Com in 2016. The following year, he joined the MBC variety show Living Together in Empty Room, which won him the Popularity Award at the MBC Entertainment Awards. Also in 2017, he landed his first TV acting gig in the SBS series Temperature of Love. In 2018, he played supporting roles in tvN’s Boyfriend and in MBN’s Fluttering Alert. In 2019, he became part of the hit tvN dark fantasy drama Hotel del Luna. In 2021, he acted alongside Lee Seung-gi and Lee Hee-joon in the tvN crime thriller Mouse.

Pyo Ji-hoon graduated from Hanlim Multi Art School in 2012. He enlisted for his mandatory military service in February 2022.