Lake Kuttara (倶多楽湖, Kuttara-ko) is a near circular caldera lake in Shiraoi, Hokkaidō, Japan. It is part of Shikotsu-Tōya National Park. The lake is recognized as having the best water quality in all of Japan. With a transparency of 19 metres (62 ft), the lake ranks second only to Lake Mashū according to the Ministry of the Environment.
Resident species of the lake include a salamander species, Hynobius retardatus (エゾサンショウウオ, Ezo Sanshōuo). Since 1909 Sockeye salmon have been introduced to the lake.