Latar belakang: Wasting merupakan kondisi anak yang berat badannya menurun seiring waktu hingga total berat badannya jauh di bawah standar kurva pertumbuhan atau berat badan berdasarkan tinggi badannya rendah (kurus) dan menunjukkan penurunan berat badan (akut) dan parah. Faktor penyebab langsung wasting disebabkan oleh asupan dan penyakit infeksi. Prevalensi balita wasting di Provinsi Lampung sebesar 7%. Sedangkan kejadian wasting di Kabupaten Way Kanan pada tahun 2021 sebesar 3.9% meningkat pada tahun 2022 sebesar 6% sehingga menjadikan Way Kanan dengan kenaikan tertinggi sebesar 153.8% dibandingkan Kab/Kota lainnya. Wasting di UPT Puskesmas Tanjung Rejo diatas cut off point yaitu 6.04%.Tujuan: Mengetahui hubungan ASI ekslusif dan riwayat penyakit infeksi dengan kejadian wasting pada balita usia 6-59 bulan.Metode: Penelitian yang digunakan kuantitatif dengan rancangan case control. Dilakukan dari Mei sampai dengan Juni terhadap 66 responden balita dan menggunakan kuesioner kemudian dianalisa secara univariat dan bivariat.Hasil: Hasil penelitian bahwa distribusi frekuensi kejadian wasting didapatkan 33 (100%) balita mengalami wasting. Dari 33 responden pada kelompok kasus sebesar 23 balita (69.7%) yang tidak ASI ekslusif dan 10 balita (30.3%) yang ASI ekslusif. Sedangkan pada kelompok kasus sebesar 15 balita (45.5%) yang ada infeksi dan 18 balita (54.4%) yang tidak ada infeksi. Ada hubungan ASI ekslusif dengan kejadian wasting dengan (p-value 0.047). Serta ada hubungan riwayat penyakit infeksi dengan kejadian wasting (p-value 0.034).Kesimpulan: Ada hubungan ASI ekslusif dan riwayat penyakit infeksi dengan kejadian wasting.Saran: Dimana perlu edukasi efektif dengan memperhatikan metode atau media yang efektif dalam pemberian materi tentang ASI ekslusif dan penyakit infeksi. Kata kunci: ASI Esklusif, Penyakit Infeksi, Wasting ABSTRACT Background: Wasting refers to a condition of a child whose weight decreases over time until his total body weight is far below the growth standards curve or weight-for-height which is low (thin) and shows acute and severe weight loss. The direct causes of wasting are poor nutrition intake and infectious diseases. The prevalence of wasting in children under five years in Lampung Province was 7%. Meanwhile, wasting in Way Kanan Regency in 2021 was 3.9%, increasing in 2022 by 6% and it makes Way Kanan Regency become the regency with the highest increase of wasting incidence (153.8%) compared to other regencies/cities. Wasting incidence at Tanjung Rejo Public Health Center UPT was above the cutoff point of 6.04%.Objective: To determine the correlation between exclusive breastfeeding and the history of infectious diseases with wasting in children aged 6-59 monthsMethods: This study used a quantitative approach with a case-control design. This study was conducted from May to June 2023 on 66 children under five years. The data were collected using questionnaires and then analyzed using univariate and bivariate data analysis.Results: The results of this study showed that based on the frequency distribution of wasting incidence, 33 children under five years (100%) experienced wasting. Of the 33 children under five years in the case group, 23 children (69.7%) were not exclusively breastfed and 10 children (30.3%) were exclusively breastfed. Whereas, in the case group, 15 children (45.5%) had a history of infectious diseases and 18 children (54.4%) had no history of infectious diseases. There was a correlation between exclusive breastfeeding and wasting (p-value = 0.047), and there was a correlation between the history of infectious diseases and wasting (p-value = 0.034).Conclusion: There was a correlation between exclusive breastfeeding and the history of infectious diseases with wasting Suggestion: Giving effective education is very necessary by paying attention to effective methods or media in providing material about exclusive breastfeeding and infectious diseases Keywords: Exclusive breastfeeding, Infectious Diseases, Wasting