沃尔巴克氏体（Wolbachia）的立克次体科的一个属的细菌，感染节肢动物，包括很大部分昆虫，以及一些线虫。它是世界上最常见的寄生微生物，可能是生物圈最常见的寄生生物。沃尔巴克氏体感染能缩短果蝇寿命。它与其宿主的交互过程很复杂，参与多种调控其寄主生殖活动的机制，有的涉及到互利共生而非寄生。有的物种如果没有沃尔巴克氏体的寄生将不能生殖甚至不能生存。研究估计在新热带界超过16%的昆虫感染了沃尔巴克氏体。全部昆虫物种的25-70%被估计是沃尔巴克氏体的潜在宿主。沃尔巴克氏菌是自然界分布最为广泛的一种共生菌，在鞘翅目、双翅目、半翅目、同翅目、膜翅目、鳞翅目、直翅目和啮目等10多个目的150万一500万种昆虫中都有共生。

Wolbachia is a genus of bacteria which infects arthropod species, including a high proportion of insects, as well as some nematodes. It is one of the world's most common parasitic microbes and is possibly the most common reproductive parasite in the biosphere. Its interactions with its hosts are often complex, and in some cases have evolved to be mutualistic rather than parasitic. Some host species cannot reproduce, or even survive, without Wolbachia infection. One study concluded that more than 16% of neotropical insect species carry bacteria of this genus, and as many as 25 to 70 percent of all insect species are estimated to be potential hosts.