Abstract: The definition of axonometric projection was re-examined. Axonometric projection is a
method by means of parallel projection, projecting the spatial coordinate system to the projection
plane along the projection direction to obtain the axonometric coordinate system and express the
spatial shape under this coordinate system. The resulting drawing is designated as axonometric
drawing. Three views represent three directions of a body respectively, and the axonometric drawing
represents three straight and three face angles with one view. The essence is to express the spatial
body on the plane. This paper further discussed some fundamental problems in axonometric
projection, such as the parallel projection system, axonometric triangle, axonometric projection
system, the basic elements and formulas of axonometric projection, analyzed the similarities and
differences between normal axonometric projection and oblique axonometric projection, and gave
their schematic diagrams.

Key words: graphics, parallel projection system, axonometric projection, axonometric drawing