Jung Yong-hwa debuted with the pop rock band CNBLUE in 2009 with the Japanese extended play Now or Never. In January 2010, they made their Korean debut with the mini-album Bluetory, which produced the hit single I’m a Loner. In March 2010, they dropped their debut Japanese studio album called Thank U. A year later, they released their first Korean full-length album titled First Step. Aside from being CNBLUE’s leader, lead vocalist, and rhythm guitarist, Jung Yong-hwa has also composed songs for the band such as In My Head and Can’t Stop. In 2015, he released his debut solo studio album One Fine Day.

Jung Yong-hwa landed his first acting role in the 2009 SBS series You’re Beautiful, which won him the New Star Award at the SBS Drama Awards. In 2011, he reunited with Park Shin-hye in MBC’s You’ve Fallen for Me, which earned him a nomination for Most Popular Actor for TV at the 48th Baeksang Arts Awards. In 2014, he starred in the tvN action sageuk Three Musketeers. In 2017, he acted alongside Lee Yeon-hee in JTBC’s The Package. In 2021, he was paired with Jang Nara in the KBS2 series Sell Your Haunted House, which scored him an Excellence Award at the KBS Drama Awards.

In 2016, Jung Yong-hwa was involved in an insider trading controversy but was later found not guilty. In 2018, he was alleged to have received preferential treatment in entering a graduate school program at Kyung Hee University. He was later cleared of all the charges relating to the allegation. He began his mandatory military service in March 2018 and was discharged in November 2019.