The literature on distal humeral supracondylar fractures does not systematically define relationships between patient characteristics and the severity or complications of these injuries. This study evaluated age, sex, height, and body mass index (BMI) in relation to fracture severity and posttreatment complications in a pediatric population. The medical records of 382 pediatric patients treated for distal humeral supracondylar fractures over a 5-year period at 1 institution were included. Variables included age, sex, height, weight, injury mechanism, fracture severity (Gartland Classification), treatment, follow-up duration, and treatment complications. Body mass index and BMI-for-age percentile were calculated. Descriptive statistics with univariate analyses and logistic regression analysis with odds ratios and 95% confidence intervals were used. Children sustaining Gartland type 3 fractures were significantly older and taller than those sustaining Gartland type 1 and 2 fractures. No significant difference existed in fracture occurrence between boys and girls. Fracture severity did not differ significantly due to sex, BMI, or BMI-for-age percentile. Severe fractures were associated with increased posttreatment complications. Complication rates did not vary significantly by age, sex, height, BMI, or BMI-for-age. Taller children aged 5 to 6 years were at the greatest risk for Gartland type 3 distal humeral supracondylar fractures. Severe fractures are associated with an increased complication risk. Sex, BMI, and BMI-for-age percentile had no effect on fracture severity or complication rates.