Workflow management system(WRMS) is a software system that supports the specification and execution of business processes. Recently, WFMS is increasingly used in industries and research organizations because the endless competition in the market compels the demand of business process automation to be highly impending. To automate business process, usually the business processes should be specified by workflow definition before the execution. However an error-comprising workflow definition might provoke serious problems to an enterprise especially when it involves mission critical business processes. So, workflow definitions should be defined in strict and rigorous way. In this thesis, we suggest a workflow definition language and analysis methods of the language to support strict and rigorous workflow definitions. Faults or mistakes like provoking access conflicts and improper specification of exceptions in workfolw definitions can be detected and notified applying the methods. The workflow definition language borrows structural constructs of conventional programming languages because they have many good features in expressing workflow processes also. For the access conflict analysis of concurrent workflow definitions, a novel technique to detect the potential read-write conflicts and write-write conflicts between activities which reads and writes to the shared variables in a workflow process definition is devised and described. WFMS quite frequently faces with exceptional situations. Hence the predictable exceptional situations need to be specified in workflow definition beforehand. Proposed workflow definition language has the features to define exceptions and a technique of analyzing uncaught exceptions in workflow definitions is developed. With slight modifications and scope restrictions, the proposed techniques can be applied to any workflow definition languages and workflow designers can define workflow processes much more concretely and safely.