Lena, IL has a population of 2,876 and is the 9,025th largest city in the United States. The population density is 1,112 per sq mi which is 400% higher than the Illinois average and 1128% higher than the national average. The median age in Lena is 43 which is approximately 14% higher than the Illinois average of 37. In Lena, 64% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 68% of Lena residents were born in Illinois, 32% were born out of state, 0% were born outside of the United States and 0% were foreign born.