Sexuality education in preschool was implemented in 2017 through Reproductive and Social Health Education (PEERS) in the Pillar of Physical Support and Health Care. Sexuality education is crucial to be implemented and applied gradually according to the children's age to shape their noble personalities, and provide them understanding. It can equip them with sensitivity and concerned about their sexual health in the future. The role of various parties, especially teachers, is comprehensible in delivering sexuality education to children effectively. Thus, this concept paper elucidates on the challenges of implementing sexuality education among preschool teachers from the aspect of teacher readiness encompassing knowledge, skills and attitudes. Based on the review, teachers' knowledge about sexuality education is at a moderate level. In addition, teachers also lacked skills in sexuality education. They are unconfident, uncomfortable and timid to share and deliver sexuality-related topics to children. Lack of specific modules, weaknesses in the implementation of the existing curriculum, parents' perceptions, cultural diversity and media influence are also challenges to teachers' readiness for effective implementation of sexuality education in preschools. Several suggestions for improvement are also presented involving various parties, such as teachers, parents, community and media, to realize the implementation of sexuality education in preschools.