The present invention provides an apparatus and method for natural language processing capable of providing an appropriate result of natural language processing. More specifically, the present invention provides a natural language processing apparatus for achieving a syntax analysis and/or a syntax generation by using natural language patterns with, at least, pattern name and pattern component. The natural language processing apparatus comprises dictionary reference means for picking up one or more natural language patterns applicable for the syntax analysis and/or the syntax generation among the natural language patterns prepared in a pattern dictionary in advance, pattern inspection means for inspecting whether the applicable natural language patterns meet a tree structure or not, and pattern application means for applying the natural language patterns to the tree structure if the natural language patterns meet the tree structure.