Structure evolution is an efficient way for service processes to perform process reconstruction. It can make good use of the existing service processes to build a new value-added service process. However, the traditional research methods of service evolution focus more on compatible substitution of the partial component services or interface parameters in the service processes. Meanwhile, the operations of structure evolution are too simple in the existing theoretical methods and fail to cope with the complex evolutionary requirements. To solve these problems, a formal method is proposed to achieve structure evolution for service processes based on logic Petri net in this paper. The service process is modeled as a service net based on logic Petri net. Several structure evolution operations are defined to deal with different evolutionary requirements. Structure normal form is introduced to evaluate the soundness of service processes. Property preservation based on the soundness of service process is also investigated by using the structure analysis and validation methods of Petri net. Finally, a framework for customization of service processes based on structure evolution is proposed and the simulation platform where evolution operations can be performed is also designed to illustrate the effectiveness of the proposed method.