Service Oriented Architecture has dynamically increased in software industry in many years ago because many advantages such as are reusable, easy to implement and loosely coupled. Service Oriented Architecture is made more concrete with web services. Web Service Business Process Execution Language (WS-BPEL) appears to solve and support more complex business processes in many enterprises. Meanwhile, mutation testing is error-based software testing in unit level which indicates efficiency of test suites. This technique is applied in many languages such as Java, C, SQL, and Ada. Weak mutation testing can reduce execution cost more than typical mutation testing. This thesis proposes a comprehensive analysis by using some mutation operators for WS-BPEL that can apply for weak mutation testing and also proposes a tool for generating mutants by using weak mutation technique. Those operators are proposed in previous work and classified in four categories of mutation operators. Those are Identifier replace operators, Activity operators, as well as Exceptional and Event operators. The proposed tool called WeMuTe that can identify dead mutants and live mutants, execution time, mutation score, and test cases effectiveness.