Diare merupakan penyakit endemis di Indonesia. Angka kematian diare paling banyak pada anak usia 5 tahun ke bawah. Jawa Barat menempati posisi pertama dalam penderita balita terbanyak. Berdasar atas data Dinas Kesehatan Kabupaten Bandung, kejadian diare banyak tersebar di Kabupaten Bandung. Wilayah kerja Puskesmas Bojongsoang mengalami peningkatan kasus diare balita pada tahun 2019. Diare disebakan oleh faktor lingkungan, faktor ibu, faktor anak, dan sosiodemografi. Studi ini bertujuan mengetahui gambaran faktor risiko diare pada balita berusia 0 - 59 bulan. Metode yang digunakan adalah deskriptif observasional dengan desain cross-sectional. Responden berjumlah 43 orang, dilakukan selama bulan september 2020 menggunakan rumus perkiraan proporsi, tingkat kepercayaan 90%, margin of error 1%, dan dipilih dengan teknik purposive. Terdapat hasil sebanyak 51% (22 orang) balita non ASI eksklusif dan 93% (40 orang) balita memiliki status gizi baik. Pada faktor sosiodemografi, sebanyak 49% (21 orang) ibu dengan pendidikan terakhir SLTP/MTS. Pada faktor ibu, sebanyak 95% (41 orang) ibu memiliki pengetahuan PHBS yang baik dan 77% (33 orang) ibu memiliki sikap PHBS yang baik. Pada faktor lingkungan, sebanyak 58% (25 orang) balita memiliki sarana air bersih yang baik dan 65% (28 orang) memiliki sarana jamban yang baik. Kesimpulan yang didapat adalah masih banyak balita non ASI eksklusif. Pengetahuan dan sikap PHBS baik, tetapi banyak ibu belum terbiasa melakukan PHBS. Masih banyak sarana air secara fisik tidak layak dan jamban yang kurang baik karena belum memiliki pembuangan kotoran sesuai aturan yang dapat menyebarkan bakteri penyebab diare. Disarankan pada institut terkait agar dapat mengajak para ibu menerapkan PHBS dan memberi ASI eksklusif.Diarrhea Risk Factors in Toddlers (0-59 Months) in Bojongsoang Primary Health Care Region in 2019Diarrhea is an endemic disease in Indonesia. Diarrhea mortality rates mostly occur in toddlers. West Java occupies the first position in most toddlers who experience diarrhea. Based on the Bandung District Public Health Office data, the incidence of diarrhea in toddlers spread in the Bandung district. In 2019, it has increased in Bojongsoang Primary Health Care region. Some of the risk factors are environmental factors, maternal factors, child factors, and sociodemography. This study was conducted to discover the risk factors for diarrhea in toddlers. During September 2020 the method used was a cross-sectional descriptive observational. A sample of 43 people was calculated by estimating proportions with a credibility level of 90%, a 1% margin of error, and were selected using purposive sampling. The results are 51% (22 people) toddlers were not exclusively breastfed and 93% (40 people) had a good nutritional status. In sociodemographic, 49% (21 people) mothers attended Junior High School. In the maternal factor, 95% (41 people) mothers had good PHBS knowledge and 77% (33 people) had a good attitude. In environmental factors, 58% (25 children) toddlers have good water facilities and 65% (28 people) have good latrine facilities. The conclusion is there are still many toddlers unexclusively breastfed. Good mother’s PHBS knowledge and attitude, but did not implement. Many poor water facilities physically and poor latrines due to unproper sewage disposal that can spread bacteria that causes diarrhea. It is suggested that the primary health care should be able to encourage mothers to apply PHBS and provide exclusive breastfeeding.