This arcade-style third-person shooter equips players with an extensive arsenal of diverse weapons, pilotable vehicles and loyal teammates in order to defeat a wide variety of attackers ranging from gigantic ants and spiders to robots and monsters standing more than 20 stories tall.

Earth Defense Force 2017 is the third game in the Chikyuu Boueigun series well know in Japan, and the first one released in North America. The game is a third-person 3D shooter featuring fights with floods of large enemies on gigantic, sprawling maps.

The game's story is set in 2017 when hordes of alien invaders attack planet Earth and the Earth Defense Force (EDF) is the only chance for human survival. The game features 53 missions where you fight againts aliens on city streets, in underground caves and on coastal zones. You have access to 170 weapons divided into 7 categories including assault rifles, rocket launchers, flamethrowers, grenades and more.

You can unlock new weapons throughout the game by picking up Weapon objects, dropped by killed enemies. Weapon objects provide you random weapons including those the character already has. On some maps there are also helicopters, battlemechs, tanks and bikes that can be controlled.

The game features 2-player split-screen multiplayer where you can play cooperative or versus battle. There is no online multiplayer however.