Use case point (UCP) method has been proposed to estimate software development effort in early phase of software project and used in a lot of software organizations. Intuitively, UCP is measured by counting the number of actors and transactions included in use case models. Several tools to support calculating UCP have been developed. However, they only extract actors and use cases and the complexity classification of them are conducted manually. We have been introducing UCP method to software projects in Hitachi Systems & Services, Ltd. To effective introduction of UCP method, we have developed an automatic use case measurement tool, called U-EST. This paper describes the idea to automatically classify the complexity of actors and use cases from use case model. We have also applied the U-EST to actual use case models and examined the difference between the value by the tool and one by the specialist. As the results, UCPs measured by the U-EST are similar to ones by the specialist.