Early Childhood Sex Education (ECSE) serves as a fundamental cornerstone for fostering the mental and physical health development of young children, as well as cultivating a well-rounded personality. The World Health Organization strongly endorses the initiation of comprehensive sexual education for children starting at the age of five. Notwithstanding, the implementation of ECSE frequently remains obscured in practical applications within our nation. Through an analytical examination of the tangible manifestations of ECSE, this study reveals critical shortcomings, including discordant conceptualizations of sexual education, the prevalence of superficial methodologies, and a notable deficiency in essential resources. Further investigation into the underlying causes of ECSE’s veiled presence discloses a confluence of deterrents: the restrictive influence of traditional ideologies, intrinsic flaws within the educational framework, the faltering efficacy of familial-academic partnerships, and a pervasive shortfall in societal cognizance. Based on a rational reflection on sex education for children, future efforts should focus on reshaping scientific perspectives to lay a solid foundation for sex education for children, improving systematic frameworks to provide support for sex education for children, building collaborative home-school cooperation to strengthen sex education for children, and enhancing legal frameworks to ensure the protection and implementation of sex education for children.