The display of geological maps on computer is an important technique ofreservoir description. With the help of computer technique, geological work can bedigitized and the level of geological research can be raised. There are the followingcommon maps in reservoir description: varions contour maps, 3 D surface maps,reservoir connecting maps, columns, reservoir sections, and so on. The paper intro-duces the ploting principles and methods for constructing these maps on computer.