A method for localizing an intracranial electrode in a subject's brain is provided. The intracranial electrode has at least one electrode contact. The method includes: acquiring a first brain image reconstructed from first image data acquired after electrode-implantation； acquiring a second brain image reconstructed from second image data acquired before the electrode-implantation； co-registering the first brain image and the second brain image to acquire spatial transformation parameters； extracting a first coordinate of the electrode contact from the first brain image； converting the first coordinate into a second coordinate in the second brain image by using the spatial transformation parameters； co-registering the second brain image and a universal brain atlas to define functional zones in the second brain image； and defining a corresponding functional zone where the second coordinate is located. Another alternative method and a system for localizing an intracranial electrode are also provided herein.
