Lyons Falls is a village in Lewis County, New York, United States. The population was 566 at the 2010 census.
Lyons Falls is located at 43°37′1″N 75°21′42″W / 43.61694°N 75.36167°W / 43.61694; -75.36167 (43.616984, -75.361750).
According to the United States Census Bureau, the village has a total area of 1.1 square miles (2.8 km), of which 1.0 square mile (2.6 km) is land and 0.1 square miles (0.26 km) (8.41%) is water.
The Black River flows through the village and is joined by the Moose River.
As of the census of 2000, there were 591 people, 238 households, and 157 families residing in the village. The population density was 602.1 people per square mile (232.8/km²). There were 294 housing units at an average density of 299.5 per square mile (115.8/km²). The racial makeup of the village was 98.82% White, 0.68% from other races, and 0.51% from two or more races. Hispanic or Latino of any race were 0.17% of the population.
There were 238 households out of which 26.9% had children under the age of 18 living with them, 48.7% were married couples living together, 11.8% had a female householder with no husband present, and 34.0% were non-families. 27.7% of all households were made up of individuals and 16.8% had someone living alone who was 65 years of age or older. The average household size was 2.48 and the average family size was 3.01.
In the village, the population was spread out with 23.7% under the age of 18, 9.3% from 18 to 24, 23.5% from 25 to 44, 26.7% from 45 to 64, and 16.8% who were 65 years of age or older. The median age was 40 years. For every 100 females, there were 110.3 males. For every 100 females age 18 and over, there were 100.4 males.
The median income for a household in the village was $27,375, and the median income for a family was $41,250. Males had a median income of $35,000 versus $21,071 for females. The per capita income for the village was $17,204. About 12.9% of families and 16.7% of the population were below the poverty line, including 16.2% of those under age 18 and 15.3% of those age 65 or over.