[1] The community was known by several alternative names, including Kanas-nu, Kanasnu, Kenasnow and Killishoo.

Killisnoo Island has long been inhabited by Tlingit people.

In the late 1800s, the North West Trading Company built a fish processing plant at Killisnoo and many Tlingit moved from nearby Angoon and other areas to Killisnoo to work at the plant.

[2] Like nearby Angoon, Killisnoo receives less rain than most of southeastern Alaska.

Killisnoo first appeared on the 1890 U.S. Census as an unincorporated village of 79 residents.