潜水母舰，是潜水舰的水面上补给舰，专为潜水舰补给燃料弹药，以及水、食物、日常用品等补给品。潜水母舰上有许多提供潜水舰上船员休息、淋浴等设施，以让长期处在水面下的船员得以有喘息的空间。

A submarine tender is a type of ship that supplies and supports submarines.

Submarines are small compared to most oceangoing vessels, and generally do not have the ability to carry large amounts of food, fuel, torpedoes, and other supplies, nor to carry a full array of maintenance equipment and personnel. The tender carries all these, and either meets up with the submarines at sea to replenish them or provides these services while docked at a port near the area where the submarines are operating. In some navies, the tenders were equipped with workshops for maintenance, and as floating dormitories with relief crews.