His early life is somewhat mysterious, with dates of his birth given in various sources ranging from 1887 to 1897; if the later date is correct he was evidently a prodigy, regarded as one of the best in New Orleans, Louisiana in his early teens. He was said to have been born in White Castle, Louisiana.
His given name was Joseph Crawford, but was adopted by trombonist Joe Petit, whose name he took.
By the early 1910s he was one of the top horn players in the new style of music not yet generally known as "jazz". He took Freddie Keppard's place in the Eagle Band (a place earlier held by Buddy Bolden) when Keppard left town.
Buddie Petit was known as a hard-drinking, fun loving man who played cornet with great virtuosity and inventiveness. He was briefly lured to Los Angeles, California by Jelly Roll Morton and Bill Johnson in 1917, but objected to being told to dress and behave differently than he was accustomed to back home, and promptly returned to New Orleans. He spent the rest of his carrer in the area around greater New Orleans and the towns north of Lake Pontchartrain like Mandeville, Louisiana, not venturing further from home than Baton Rouge and the Mississippi Gulf Coast.
Okeh Records offered him a chance to record on their 1925 field trip to New Orleans, but Petit held out for more money and was never recorded. Musicians such as Danny Barker and Louis Armstrong have said that it is a great loss to jazz history that there are no recordings of Petit.
Some of his contemporaries said that Louis Armstrong's record "Cornet Chop Suey" is the closest to Petit's style and sound of anything put on record.