Pain is an unpleasant sensory and emotional feeling accompanying existing, impending, or potential tissue damage. Valid pain assessment and standardized pain documentation are important in oncology pain management; however, they are still deficient. Thus, we developed a pain assessment and record information system for nurses in the oncology department and implemented a questionnaire survey to evaluate users' acceptance of the system. The pain assessment system focused on usability and efficiency to provide a modified workflow that was safe, less time-consuming, patient centered, enjoyable, and efficient. The pain assessment and record chart types in the system enabled greater standardization of pain assessments and records. The application of the system greatly improved the efficiency of nursing in the oncology department, guiding nurses in an accurate and comprehensive patient pain assessment and contributing significantly to further improvement in pain care standards and care decisions. Nurses and doctors surveyed reported a high degree of satisfaction with factors such as saving time and improving the capacity of pain control, suggesting that the system enhanced the quality of pain management. Through this system, we can promote pain management, improving care quality for patients.