Great American Cockroaches, colloquially called radroaches or simply giant cockroaches are obviously giant versions of the regular cockroaches mutated by radiation - there was never any doubt that they would survive a nuclear war. Found mainly in underground areas and sewers, these creatures can usually be found in fairly large groups. They feed on the dead, but will go after living creatures if isolated. Their numbers are usually their greatest advantage. Radroaches live mostly in the areas east of California.

It is said that cockroach guts are actually useful in the treatment of radiation poisoning, and are widely used by tribals for that purpose.


Capital Wasteland编辑

Radroaches look similar to real life roaches in the Capital Wasteland, the only mutations they experience being through size, in which they become the size of a house-cat. They are typically the weakest enemy in the game despite bloatflys, dying from one hit from most weapons, save from a BB gun with very low skills.The best way is to have a .32 Pistol or Chinese Pistol, to not waste ammunition or time . They also are one of the few 'hostile' creatures that will not charge a player, initially, even though marked such on the compass and reticule. In fact, when sneaking, if a Radroach spots the player, the [HIDDEN] notifier will, more often than not, change to [DETECTED], rather than [DANGER] or [CAUTION].

Radroaches will attack, however, if the player seems to threaten them, either by having a weapon drawn, invading their territory or it will attack almost any time, when you are in battle with another enemy (which is limited to less than a foot around the creature), or attacking them. Generally, they will spread their wings in warning when they're about to attack. Companions will attack them even when they don't attack or provoke the player.

Two named cockroaches appear in Fallout 3: Fluffy and Jitters.


Mini-FOT Logo.png以下内容基於Fallout Tactics,因而一些細節可能與正史相沖突。

In the Midwest, cockroaches are a common sight in the wasteland. Like in the Capital Wasteland, they can be encountered nearly everywhere, from old buildings to plains. However, they are drastically different and more dangerous than those met in Capital Wasteland. They have a big, protected main body and small legs, and their juice is incredibly poisonous. They are very aggressive and attack every human unlucky enough to encounter them.

The Midwestern radroaches are more varied than their Capital Wasteland cousins. Three variations are known:

Small cockroach编辑

The weakest of the cockroaches, they can be easily killed even by a tribal. However, their bites can poison an opponent, and when they are in large groups, they can kill even a prepared combatant. This type of roaches is nearly the same size as their "relatives" in Capital Wasteland.

Large cockroach编辑

They are very similar to their small cousins, but are larger (being approximately the same weight as human) and have an ability to spit their poisonous juice.


Roachor is a unique mutant cockroach encountered by the Warrior of Midwestern Brotherhood of Steel. He is an "advanced" version of a large cockroach, who lived in Peoria facility. It appears Roachor was affected by the high amount of radiation coming from a strange production device which was used in manufacturing fission batteries. He is even bigger than any large cockroach, being the same size as a car, his body being radioactivly-greenish and his poison even deadlier. However, the warrior succeeds in killing him.




In Texas, a bizarre cockroach mutation can be found. They have an orb-like main body with a small head and six limbs with a claw on the end of each. When attacking, they leaps towards and claw or bite a targeted creature - dodge quickly to avoid these pests, as they are very mobile. Their appearance is not very cockroach-like and they apparenly have a set of human-like teeth and two fish-like eyes. In fact, these creatures somehow look like spiders. Another strange fact is that they also have an appendage somewhat resembling a tail. These bugs are known to roam the wastes, many of them could be found in such radioactive place like Carbon crater, but their "home" is probably the Secret Vault, where the majority of them could be found. A possible explanation of their existence is that they were made by modified strain of FEV located in Secret Vault, being a result of biological weapon experiments conducted by the Vault scientists and now, after the Vault's downfall, they found their way to the wasteland.

They are divided in two main sub-species:

Small Radroach编辑

These are most common of them. Beside Secret Vault, some of them made their home in Carbon crater, while other are found in the Carbon Mill and later in Los. They are roughly the same size as a dog. Some of these critters have a green exoskeleton and could be carried inside their bigger comrades.

Big Radroach编辑

These are bigger versions of their smaller counterparts, being the same size as Brahmin. Aside from the Secret Vault itself, these pests are found near their home, in Vault-Tec Warehouse, guarding the Secret Vault and participating in battles between the Super Mutants and the Church of the Lost. In Secret Vault, some of them have a sort of web and spikes generated around their limbs and body and, more important, are protected by a green exoskeleton shell. Some of them also could carry a number of their smaller relatives inside themselves.


Giant cockroaches appear in Fallout Tactics, Fallout: Brotherhood of Steel, and were to appear in Van Buren. They were also mentioned in Fallout Bible 1. Radroaches appear in Fallout 3.


  • The Radroach, according to an Enclave Officer's Field Research Terminal, is indeed descended from average American cockroaches. Furthermore, it also determines their Scientific Denomination to be Animalia, Arthropodia, Insecta, Blattodea, Blattidae, Periplaneta ( )
  • All Radroaches that appear in Fallout 3 are male. Apart from one pair of big appendages (so called cerci) they possess another pair of smaller appendages called styli that is characteristic for male cockroaches. (see Identification on
  • It is recommended to carry a weak weapon with you, such as a 10mm pistol, to kill radroaches to avoid using up scarce ammunition for your more powerful weapons. A shot from a 10mm pistol will usually kill a radroach in a single shot anyway.
  • Using hand-to-hand combat is the most effective method. Using this will show a unique combat move, the 'roach stomp'.
  • In a rare case, they have been found to be un-hostile, or show up on your radar as a green bar rather than red. This has been seen in a few select subway tunnels, it seems that they are usually friendly if they are skittering towards a set waypoint. However this may be a bug. *pun*, it is however an actual feature that radroaches will register with the "Detected" sneak status if you keep your distance, moving closer will trigger the hostile responses.

(PS3) Although they will not target the player, in a few metro tunnels the 'friendly' radroaches will target feral ghouls, often killing them.

  • The roach's mutation contradicts popular beliefs that state that a cockroach would be the only creature to remain unharmed or unchanged by radiation