Organoids are three-dimensional (3D) cell cultures that replicate key structural and functional aspects of human organs. Derived from stem cells or tissue explants, organoids offer significant advantages over traditional two-dimensional (2D) cultures and animal models by more accurately simulating human physiology. Organoids have been successfully developed for various organs, including the brain, kidney, liver, and breast, providing valuable insights into organ biology, disease modeling, and drug discovery. Brain organoids, in particular, closely resemble the cellular composition and anatomical structure of the human brain, making them valuable models for studying brain development and neurological disorders. In this chapter, we focus on the application of brain organoids in disease modeling and discuss the current limitations of organoid technology.