The Green Brain (1966), initially published as Greenslaves, is a science fiction novel by American writer Frank Herbert.

The "Green Brain" of the title is an intelligent organism that embodies and arises from nature's resistance to human domination.

It is able to command social insects to form humanoid-shaped collective organisms which it uses to infiltrate the "Green Zone".

The book is about a small team sent into the jungles of Brazil to investigate the problem, who find out that some of their assumptions were wrong.

[2] By the time of Herbert's death, arrangements also had been made to make a movie adaptation of the novel.