Integrated curriculum is a popular curriculum design used in organizing preschool curriculum. This study aims to analyze how teachers design an integrated curriculum. Specifically, it describes: (1) how do teachers plan an integrated curriculum; (2) what common themes are used; and (3) what factors are influential or considered in integrating the curriculum. Since the study was conducted in a Christian school, it also analyzes the influence of the Christian faith in the curriculum. Curriculum analysis and focus-group discussion with preschool teachers and administrators were done to gather the necessary data for the study. The results of the study show that the thematic approach is dominantly used in integrating the curriculum. The themes usually derived from big ideas or topics related to science, social studies, and some concepts and activities that are interesting to the learners. Several factors are also found to be influential in designing the curriculum. The study also found out that Christianity has a great impact or influence in designing the curriculum. Biblical stories, and Christian values are always integrated in the selection of sub-topics and activities in the curriculum.