- Yellow fever: During the 19th century, yellow fever was a major public health problem in New Orleans and other parts of the state, causing several epidemics.
- Youngsville: Youngsville is a town in Lafayette Parish, Louisiana, located about 10 miles from Lafayette, the parish seat.
- Yams: Louisiana is known for its production of sweet potatoes, locally called yams. The state produces various varieties of sweet potatoes, including the Beauregard variety which is especially popular.
- Youth sports: Louisiana has a strong tradition of youth sports, with participation in sports like football, basketball, baseball, and softball being popular among young athletes across the state.
- Yum Yum Donuts: Yum Yum Donuts is a popular donut chain based in New Orleans. It is known for its variety of donuts, including its signature "Beignets".