Communication disorders following traumatic brain injuries are different from those caused by aphasia. These disorders are classified into formal and semantic problems of utterances, and ego-centric and disinhibited remarks. These problems are analyzed by discourse analysis and pragmatics, but standardized assessment methods have not been developed. Among the neuropsychological symptoms, the executive functions, especially planning, monitoring, abstraction skill, inhibition, and attention, and visual perception are associated with these communication disorders. Development of appropriate therapy methods for treating these problems is needed.