MDX is a language that expresses selections, calculations, and some metadata definitions against an Online Analytical Processing (OLAP) database. As the user interface with OLAP, the MDX complier is a major component of the OLAP analysis server. This paper addresses the system design of MDX compiler via the ADD method, meaning that system requirements, including functional and quality requirements and constraints, are considered as drivers in the design process. The output architecture satisfies not only that the functional requirements but also the important qualities the system must possess.