Greenfield Public Square Historic District is a nationally recognized historic district located in Greenfield, Iowa, United States.

There is a significant number of one- and two-story, brick, commercial buildings, as well as a few three-story structures.

Besides the courthouse, the other buildings that are individually listed on the National Register include Warren Opera House Block and Hetherington Block (1896), Adair County Democrat-Adair County Free Press Building (1903), and the Hotel Greenfield (1920).

It is a Lancaster Square, of which there was only one other in an Iowa county seat, Fort Dodge.

Building numbers begin on the west side of South First Street with 102 and follow clock-wise around the square ending at the east side of South First Street with 362.