A juice bar is an establishment that primarily serves prepared juice beverages such as freshly squeezed or extracted fruit juices, juice blends, fruit smoothies (a thick fruit drink, often iced), or other juices such as fresh wheatgrass juice. Sometimes other solid ingredients or nutritional supplements may be added as boosters, such as fresh bananas, nuts or nut butter, bodybuilding supplements, soy protein powder or others such as whey or hemp protein powders, wheat germ, or spirulina or chlorella. Also if less juice is used with these same ingredients drinks called health shakes may be produced.

Juice bars share some of the characteristics of a coffeehouse, a soda fountain, a café, and a snack bar, such as providing blended drinks and food, such as sandwiches. Juice bars may be standalone businesses in cities or located at gyms, along commuter areas, near lunchtime areas, at beaches, and at tourist attractions. In Mexico, juice bars have become more popular in the 2000s. Mexican juice bars often also sell healthy beverages and snacks.