1. A workflow processing system comprising: a workflow managing unit configured to register or store a workflow; a resource list generating unit configured to generate a resource list relating to a part or whole of resource to be used in the workflow; a resource instructing unit configured to instruct which resource either upon workflow registration or upon workflow execution is to be used for each resource in the resource list; a resource acquiring unit configured to acquire the resource upon workflow registration, when the resource instructing unit has received an instruction to use the resource upon workflow registration; and a workflow executing unit configured to interpret and execute the workflow that has been stored in the workflow managing unit, wherein if the resource upon workflow registration is acquirable by the resource acquiring unit, the workflow executing unit executes the workflow using the resource that has been acquired by the resource acquiring unit, and wherein if the resource upon workflow registration is not acquirable by the resource acquiring unit, the workflow executing unit executes the workflow using the resource upon workflow execution.