Purpose: This study aimed to assess the association between caregiver’s level of type 1 diabetes (T1D) nutrition knowledge with children’s dietary diversity score (DDS), mean intake of macronutrients, nutrient adequacy ratios (NARs) and mean adequacy ratio (MAR). Research Design and Methods: A cross-sectional analytical study design was used. The study was conducted at 6 diabetes clinics in Uganda among 59 caregivers and 61 children. T1D nutrition knowledge survey (NKS) was used to assess the caregiver’s nutrition knowledge, and the 24-hour dietary recall and dietary diversity score (DDS) questionnaires were used to collect data on the child’s dietary intake. Results: Majority (93.2%) of the caregivers had low T1D nutrition knowledge. Carbohydrate counting was the least performed nutrition knowledge domain. The children’s mean DDS, calorie intake and MAR were 5.7 ± 1.6, 666.7 ± 639.8 kcal and 0.7 ± 0.3, respectively. The mean NARs of carbohydrate, protein, and fat were 0.9 ± 0.3, 0.9 ± 0.4, 0.5 ± 0.5, respectively. There was a significant association between DDS with NARs of carbohydrate, protein, fat, vitamins A, B2, B3, B5, B12, folic acid, zinc and MAR. No formal education was significantly associated with a lower mean NKS score among caregivers (p = 0.039). Caregivers’ T1D nutrition knowledge, age and family size explained 14% of variation in the child’s dietary diversity (p = 0.041). Conclusion: Despite poor nutrition knowledge among caregivers especially on carbohydrate counting, dietary diversity among children with T1D remained favorable. Excess carbohydrate intake was observed with inadequate intake of proteins, fats and micronutrients (vitamin A, B vitamins and calcium). Caregivers with low education were more likely to register poor nutrition knowledge; therefore, there is need to develop and tailor nutrition education programmes to enhance comprehensive learning among caregivers for improved outcomes.