Children's intuitive understanding of numbers begins early in life, and their numbers-related knowledge influences instructors' teaching practices. The number zero is more difficult to teach and learn than other numbers. The purpose of this study was to investigate how preschool teachers perceive the number zero and design their teaching practices for it. The participants in this case study were selected through convenience sampling. The findings indicated that the majority of the participating preschool teachers perceived the number zero as a symbol and considered children's age while developing teaching practices.