Abstract: Product with complicated forms has perplexing workflow in design, manufacture and market analysis and its workflow has high uncertain specialty, hence a workflow management system (WMSs) with more flexibility will be required. This implies that a workflow having dynamic, distributed and intellectualized characteristic be introduced into, but uncertain specialty will occur in system, thereby evaluating its reliability is an important aspect in workflow schemn. An approach for analyzing workflow, is presented, modeling relationships among tasks in workflow; providing a method for calculating resource consumption and uncertain specialty of flows is provided; a method for detecting cycle included in the system is be given; subsequently, a approach for evaluating system reliability is be drawn sown, A case study, relating the experimental platform, will exemplify the introduced approach.

Key words: Dynamic, Reliability, Resource consumption, Workflow