火山口湖（Crater Lake），中文又译魁特湖，是位于美国俄勒冈州的一个火山湖。属火山口湖国家公园管区范围内。火山口湖以其深蓝色的湖水和很高的透明度而闻名。火山口湖最深的部份达655公尺（2,148英呎），火山口约是在7,700年（±150年）前马札马火山喷发时形成。

在1853年6月12日，约翰·卫斯理·希尔曼（John Wesley Hillman）成为第一个发现火山口湖的人，他当时将之命名为「深蓝湖」（Deep Blue Lake）。火山口湖至少改过三次名，如蓝湖（Blue Lake）、庄严湖（Majesty Lake），最后才确定使用现在的名称火山口湖。火山口湖是美国最深的湖泊，在世界湖泊深度中排名第9位。

Crater Lake (Klamath: giiwas) is a caldera lake in the western United States, located in south-central Oregon. It is the main feature of Crater Lake National Park and is famous for its deep blue color and water clarity. The lake partly fills a nearly 2,148-foot (655 m)-deep caldera that was formed around 7,700 (± 150) years ago by the collapse of the volcano Mount Mazama. There are no rivers flowing into or out of the lake; the evaporation is compensated for by rain and snowfall at a rate such that the total amount of water is replaced every 250 years. With a depth of 1,949 feet (594 m), the lake is the deepest in the United States. In the world, it ranks tenth for maximum depth, and third for mean (average) depth.