A sleeve tattoo (or tattoo sleeve) is a large tattoo, or a collection of smaller tattoos, usually themed in similar manner, that covers most or all of a person's arm, usually from shoulder to wrist.

The term "sleeve" is a reference to the tattoo's size similarity in coverage to a long shirt sleeve on an article of clothing. In this manner, the term is also used as a verb; for example, "getting sleeved" means to have one's entire arm tattooed. The term is also sometimes used in reference to a large leg tattoo that covers a person's leg in a similar manner.

Half-sleeves or quarter-sleeves are tattoos that cover only part of an arm, usually above the elbow, but can also be found below the elbow. A sleeve implies complete tattoo coverage of a particular area, so a half sleeve is a tattoo that covers the entire upper or lower arm. A "quarter sleeve" usually covers the area of skin from the shoulder midway to the elbow.

Sleeve tattoos are a collaboration between a tattoo artist and customer to demonstrate a personal and unified artistic theme. Other times, a sleeve is created when a person has many smaller tattoos on his/her arm and later has them connected with background tattooing to form a sleeve. Pre-planned sleeves generally require many long hours of tattooing and can take weeks, months or years to complete.

Some organizations have proposed rules banning sleeves among their members; the United States Marine Corps prohibited Marines from getting arm- or leg-sleeve tattoos after April 1, 2007. Those with sleeves already are protected under a grandfather clause. Nevertheless, tattoo sleeves have become so popular that several clothing companies have produced apparel that simulates the look of tattoo sleeves using transparent mesh fabric printed with tattoo designs.