"Good Girl" is a song recorded by American country music singer Dustin Lynch. It was released on May 2018 by Broken Bow as the lead single from his fourth studio album Tullahoma (2020). Lynch wrote the song with Justin Ebach and Andy Albert, and Zach Crowell produced it. It's about a woman that Lynch describes as being perfect and has changed him for the better. "Good Girl" gave Lynch his sixth number one hit on the Billboard Country Airplay chart, as well as his first as a writer. It also peaked at numbers eight and 44 on both the Hot Country Songs and Hot 100 charts respectively. It has sold 83,000 copies in the United States as of January 2019. The song achieved similar success in Canada, reaching number 11 on the Canada Country chart. An accompanying music video for the song, directed by Mason Dixon, tells a story inspired by Bonnie and Clyde.
Lynch released the single in mid-2018 following the poor chart performance of his previous single "I'd Be Jealous Too". He said in a video posted to Instagram that he asked label executives for permission to release the single in order for it to be successful in the summertime, and they approved of the choice. Rolling Stone described the song as "continues Lynch's flirtation with R&B vibes but trades the EDM beats of ['I'd Be Jealous Too'] for a laid-back tune about having found the right kind of love, one with the potential to last beyond the upcoming summer season." The Boot wrote that the song "is an ode to Lynch's love" and "Throughout the summery, upbeat track, Lynch explains just how perfect she is, and how she's changed his world for the better."