Cruz Bay is the main town on the island of Saint John in the United States Virgin Islands.

Cruz Bay, located on the west coast of Saint John, is the island's largest commercial center and the location of the main port on Saint John. The primary access to Saint John is through Cruz Bay Harbor. Frequent barge and ferry, including car ferry, service connects Saint John to the neighboring more-developed island of Saint Thomas. Ferries also run regularly between Cruz Bay and Tortola, Virgin Gorda, and Jost Van Dyke in the British Virgin Islands.

Cruz Bay is home to numerous shops and restaurants which are frequented by tourists and locals alike. The Virgin Islands National Park Visitor Center, the Elaine Sprauve Library, a post office, and a bank are also located in Cruz Bay.