Lake Catherine, IL has a population of 1,888 and is the 11,366th largest city in the United States. The population density is 2,072 per sq mi which is 832% higher than the Illinois average and 2187% higher than the national average. The median age in Lake Catherine is 42 which is approximately 11% higher than the Illinois average of 37. In Lake Catherine, 53% of the population over 15 years of age are married, 97% speak English and 2% speak Spanish. 84% of Lake Catherine residents were born in Illinois, 12% were born out of state, 0% were born outside of the United States and 4% were foreign born.