While improving the operational efficiency of a casualty insurance department in the property insurance industry has been extensively investigated, increasing the performance and efficiency of an underwriting department in a life insurance company is relatively unexplored. The paper studies the improvement of efficiency of the casualty insurance department. The research focuses on how a non-life insurance company should change in order to improve the efficiency of its casualty insurance department from five different factors, which are artificial intelligence (AI) and robots, core systems, internal business processes and delegation of authority policy, employee training, and distribution channels and marketing strategies. Interview information from the participants is categorized in order to ascertain the respondent’s opinions are presented correctly. The findings suggest that property insurance companies could consider using AI or robots, introducing a new core system, giving a higher limit of authorities or delegation of authority for its branches to underwrite more insurance products, and providing training that employees needed to handle daily business routines. These findings have implications for non-life insurance companies to have plans or intend to evaluate what things they should do to increase performance and competitiveness from different perspectives.