Latar Belakang : Tahun 2022, angka kasus demam berdarah di Provinsi Bali meningkat sebesar 132 kasus per 100.000 penduduk. Penularannya melalui gigitan nyamuk, terutama nyamuk Aedes aegypti ke manusia. Dukungan keluarga mempunyai peranan penting dalam pencegahan DBD, perilaku anak bergantung pada dukungan keluarga yang diberikan selama bersama keluarganya. Tujuan : Untuk mengetahui hubungan dukungan keluarga dengan perilaku pencegahan Demam Berdarah Dengue (DBD) pada anak usia sekolah kelas IV dan V di lingkungan SD Negeri 2 Sesetan. Metode : Penelitian ini menggunakan analitik korelasi dengan pendekatan cross sectional study. Sampel penelitian sebanyak 182 siswa siswi yang diperoleh dengan teknik probability sampling tipe stratified random sampling. Hasil : Dari 182 responden mayoritas mendapatkan dukungan keluarga cukup sebanyak 80 responden (44,0%) dan sebagian besar memiliki perilaku pencegahan cukup sebanyak 88 responden (48,4%). Hasil uji spearman’s rho menunjukkan pvalue

Background: In 2022, the number of dengue fever cases in Bali increase by 132 cases per 100,000 population. It is transmitted through mosquito bites, especially the Aedes aegypti to humans. Family support has an important role in preventing dengue fever, the children’s behavior depends on the family support provided in their family. Purpose: To determine the correlation between family support and dengue fever preventive behavior on school age children at fourth grade and fifth grade students in SD Negeri 2 Sesetan. Methods: This research employed analytical correlation with cross sectional study. There were 182 students were recruited as the samples which were chosen by using probability sampling technique such as stratified random sampling. Findings: The result showed that out of 182 respondents, there were 80 respondents (44,0%) had sufficient family support and 88 respondents (48,4%) had moderate preventive behavior. The result of Spearman’s rho test showed p-value