The practical applications of workflow management system (WFMS) demand that WFMS should support dynamic changing. To satisfy this request the designing model of traditional workflow must be improved. In this paper

a dynamic three dimensional meta-model is proposed. The meta-model is derived from the traditional laws of building model and the laws of changing. Alter re-surveying a three dimensional workflow model

which comprises process model

organization model and information model

the meta model describes the dynamic characteristics behaving in objects of process

activity

activity attributes and organization

A workflow model educed from this meta-model will possess the ability of interacting with hrunan and the ability of handling dynamic changing. The meta-model works in the way that it defines the dynamic characteristics as many as possible at the design stage and the changes in run-time can be confined in the pre-defined schema.This approach will enable WFMS to be flexible without losing the process control.