Abstract Background Acute malnutrition in children <5 years of age has a direct relationship with medical complications and mortality. We aimed to describe the etiologic factors in children with moderate and severe non–illness‐related acute malnutrition who required hospitalization for treatment of malnutrition in two high‐complexity hospital centers in Bogotá, Colombia. Methods This is a multicenter case series (December 2016 to December 2020) including patients aged 1–59 months with a weight/height indicator less than −2 SD. Electronic health records were reviewed, and demographic (sex, age, city of origin, and socioeconomic status) and clinical data (gestational age at birth, edema, and nutrition status) were collected. Descriptive analysis of information was performed. An exploratory bivariate analysis by diagnostic categories of moderate and severe acute malnutrition vs days of hospitalization was also performed. Results Forty‐five patients were included, 62.2% of whom were male, with a median age of 14 months (Q1–Q3: 7–24). The main etiologic factors of malnutrition were related to problems with total food intake (33.3%), transition in consistency of feeding (31.1%), and breastfeeding technique (22.2%). Only 13.3% had problems related to food insecurity. There were no statistically significant differences between moderate (median: 7 days; Q1–Q3: 5–12) and severe (median: 8 days; Q1–Q3: 5–16) acute malnutrition when compared by days of hospitalization. Conclusions The main etiologic factors of malnutrition in our study population were related to problems in the amount of food provided and transition in consistency of complementary feeding.