This paper presents a rapid scenario-based system generation for process control. Each scenario represents a business rule. By decoupling business rules from functional components, one not only can reuse the components but also can reuse the business rules patterns, which repeatedly appear in different process control. For example, a process control may use a same business rules pattern with different alternative components to optimize system configuration in terms of quality, cost, and efficiency; or use several basic business rules patterns to compose a new process control for a new production line. To rapidly and adaptively develop process control automation, this paper proposes scenario-based pattern-oriented approach to generate quality code to process business rules for process control. The approach allows a user to use visual tools of flowchart to specify business rules, and update system configuration. A variety of analyses can be performed to verify the business rules before design and implementation. This research provides two approaches to execute process control: 1) script-based approach; and 2) compiler-based approach. Both approaches can handle concurrent, synchronous/asynchronous computation. When there is a change, a user needs only to modify flowchart, while the code is generated automatically. In addition, test scenarios/scripts are generated from the scenario-based business rules to test the execution results to ensure the quality of code generated.