Aims: To examine the effect of pump vs injection therapy on the lipid profile of children with Type 1 diabetes mellitus. Methods: A cross-sectional analysis of the lipid profile of children aged ≤ 18 years with Type 1 diabetes mellitus from SWEET, an international diabetes registry, was conducted with a focus on the effect of treatment regimen. Dyslipidaemia was defined as LDL cholesterol ≥2.6 mmol/l or non-HDL cholesterol ≥3.1 mmol/l. LDL and non-HDL cholesterol values among 14 290 children (52% boys, 51% receiving pump therapy) from 60 SWEET centres were analysed by linear and logistic regression analysis adjusted for sex, age, diabetes duration, HbA1c and BMI-standard deviation score group, region, and common interactions between age, sex, HbA1c and BMI. Results: This study confirmed the established associations of increased lipids with female sex, age, diabetes duration, HbA1c and BMI. LDL and non-HDL cholesterol levels were lower in the pump therapy group compared to the injection therapy group [LDL cholesterol: injection therapy 2.44 mmol/l (95% CI 2.42 to 2.46) vs pump therapy 2.39 mmol/l (95% CI 2.37–2.41), P<0.001; non-HDL cholesterol: injection therapy 2.88 mmol/l (95% CI 2.86 to 2.90) vs pump therapy 2.80 mmol/l (95% CI 2.78–2.82), both P<0.0001]. Similarly, the odds ratios for LDL cholesterol ≥2.6 mmol/l [0.89 (95% CI 0.82–0.97)] and non-HDL cholesterol ≥3.1 mmol/l [0.85 (0.78 to 0.93)] were significantly lower in the pump therapy group, even after all adjustments. Conclusions: Our results indicate that pump therapy is associated with a better lipid profile.