Harlen is a spelling of Harlan, an English surname taken from place names that are usually explained as "hare land", from the Old English hara and land. The name has an old-fashioned Southern ring in the United States, where it was in modest use through the 20th century. Harlen itself has been remarkably steady, never leaving the band between number 2199 and 2564 over the last decade; it ranks number 2338 in 2025.