ABSTRAK Latar belakang: Kurangnya pemahaman terhadap pendidikan seksual terutama underwear rules pada anak prasekolah, dapat membuat pemahaman kesehatan reproduksi mereka rendah atau lemah dan berdampak buruk sehingga sering dijumpai kekerasan seksual pada anak. Sosialisasi pengetahuan underwear rules dapat dilakukan dengan cara terapi bermain metode bernyanyi dan terapi bermain menonton video yang ditujukan agar anak dapat memahami bagian pribadinya yang boleh dan tidak boleh disentuh serta salah satu bentuk pencegahan kekerasan seksual pada anak. Metode : Penelitian ini menggunakan metode kuantitatif dengan desain quasi eksperimen menggunakan pre-post test design with control group. Sampel penelitian dipilih dengan purposive sampling dengan kriteria inklusi dan eksklusi. Responden berjumlah 52 orang yang dibagi menjadi kelompok intervensi yang diberi perlakuan terapi bermain metode bernyanyi dan kelompok kontrol yang diberi perlakuan terapi bermain metode menonton video. Hasil : Hasil penelitian menunjukan bahwa terdapat perbedaan rata-rata nilai pengetahuan anak pada kelompok intervensi dan kelompok kontrol. Hasil uji statistik menunjukan adanya pengaruh terapi bermain metode bernyanyi dengan terapi bermain menonton video p value sebesar 0,000 (p value ? ? 0,05). Kesimpulan: Sosialisasi underwear rules menggunakan terapi bermain metode bernyanyi lebih efektif untuk digunakan sebagai pendekatan meningkatkan pengetahuan pada anak usia pra sekolah. Kata kunci: Pengetahuan, underwear rules, terapi bermain, bernyanyi ABSTRACT Background: Background: Lack of understanding of sexual education, especially underwear rules in preschool children, can make their understanding of reproductive health low or weak and have a bad impact so that sexual violence in children is often encountered. Socialization of underwear rules knowledge can be done by means of play therapy, singing methods and video watching play therapy aimed at children so that children can understand their personal parts that can and cannot be touched and a form of prevention of sexual violence in children. Methods: This study uses a quantitative method with a quasi-experimental design using a pre-post test design with control group. The research sample was selected by purposive sampling with inclusion and exclusion criteria. The respondents were 52 people who were divided into an intervention group that was given play therapy treatment using the singing method and a control group that was given play therapy treatment using the video viewing method. Results: The results of the study showed that there was a difference in the average value of children's knowledge in the intervention group and the control group. The results of the statistical test showed that there was an influence of the singing method play therapy with the play therapy watching videos with a p value of 0.000 (p value ? ? 0.05) Conclusion: Socialization of underwear rules using play therapy, singing methods is more effective to be used as an approach to increase knowledge in preschool children. Keywords: Knowledge, underwear rules, play therapy, singing