Worlds are the locations in LEGO Universe. Worlds can be traveled to by rocket, or on occasion, through teleporters. During Alpha and Beta, only Venture Explorer, Avant Gardens, Nimbus Station, Gnarled Forest, Forbidden Valley , Club Station Alpha , and for a short time Starbase 3001 were available in addition to the five starter properties. Each world has at least one Vendor, one Mission, and one NPC. There were many other worlds planned to be placed in Lego Universe, but because of Lego Universe's closure, all future worlds were canceled.
- The Venture Explorer- The tutorial level, players learn the controls and gain Imagination here.
- Avant Gardens- A public park area turned into a warzone after an experiment gone wrong. Players get a brief outline of all four Factions while walking through Avant Gardens.
- Nimbus Station- Serves as a hub world. Nimbus Station is where players join factions. Almost every world intersects on Nimbus Station.
- Pet Cove- A small lighthouse area where players learn to tame pets.
- Gnarled Forest- A forest area with a racetrack, home of the pirates. It also has Stromling Apes, Stromling Pirates, and Stromling Admirals.
- Forbidden Valley- Home of the ninja and the terrifying Dark Ronin. Other enemies include Maelstrom Horsemen and Maelstrom Dragons.
- Starbase 3001- An LUP space station above Nimbus Station that acts as a hub world for the LUP worlds.
- Property Worlds- Sub-Worlds that players can place models on and build custom models with bricks. There are individual sub-worlds for each main world with themes that attribute to the main; each player can claim one and can choose whether it is public, private, or for friends only.
- Moonbase - A base on a moon, crawling with the scorpion-like Grabble aliens. It was created by the American LUP Team Alpha. Players can access it through Starbase 3001
- Portabello- Portabello was created by LUP Team Brickazon. Though both Robot City and Deep Freeze made appearances at BrickCon 2010, Portabello did not. The world is now out and the main characters are petite dragons. It is accessed through Starbase 3001.
- DeepFreeze- DeepFreeze is made by the LUP Team Luptario. Contains a frozen river and maelstrom beavers. Accessed through Starbase 3001.
- Robot City- Robot City is made by the LUP Team DeerBite. This world has robotic civilians, both Maelstrom-infected and uncontaminated. Accessed through Starbase 3001
- Frostburgh- A village located on a comet that orbits around the Nimbus System. Once a year, its orbit brings it close to Nimbus Station. This closeness marks the celebration of Frostivus.
- Crux Prime- The biggest chunk of planet Crux that contains all enemies from Avant gardens, Gnarled Forest, and Forbidden Valley but in a stronger, newer form. Players can learn the art of Spinjitzu from Neido here.
- Nexus Tower - Nexus Tower is the Nexus force command center. It holds the last shard of pure Imagination. There is a floor for each faction and players are able to see the Faction Leaders here. It also contains the portals to Club Station-Alpha, Starbase 3001, and Crux Prime.
- Ninjago Monastery - A monastery on the planet Ninjago. Lots of Skullkin dwell here. Players access more Spinjitzu by learning from Sensei Wu and his ninjas.
These worlds are relevant only to the LEGO Universe story and cannot be played.
- Gallant 5- A structure built by the First Builders is here.
- Planet Crux- The original planet that was shattered to become the Nimbus System.
- Ninjago- A planet created by the First Spinjitzu Master, and the main setting for the Ninjago story arc in LEGO Universe.
- Wonderland- The pre-alpha equivalent of Planet Crux, a mystical area that contained all the smaller worlds.
These are worlds that were planned at one point in the game's development, but were removed from the game or replaced by another world.
- Nimbus Park- Replaced by Avant Gardens. A public park with infected Robot Mower enemies.
- YouReeka- Replaced by Nimbus Station. A town infested with skunks.
- Pet Ranch- Replaced by Pet Cove. A farm where players could learn to tame pets.
- Tarrano Forest- Very little is known about this world. It was possibly dinosaur themed.
- Creepy Crawly Forest- A haunted forest filled with bugs.
Worlds that would have been released in 2012 and beyond. But due to the closure of LEGO Universe, they will not be released.
- Kingdoms World - An castle world set for release in 2012.
- Fire Temple - An unreleased Ninjago world based off of the fire element.