The aim of this study is to investigate the role of mother’s knowledge and socioeconomic status (SES) of the family on glycemic control in diabetic children. Our sample was taken from successive admissions to the outpatient’s diabetes clinics in Tuzla, Bosnia and Herzegovina. Diabetes knowledge was assessed using the Michigan Diabetes Research and Training Center Diabetes Knowledge Test. Glycemic control was assessed by glycosylated hemoglobin (HbA1C). The mother’s demographics were obtained by self-report. To categorize families’ SES, parents’ level of education, and current employment were recorded and analyzed using the Hollingshed two-factor index of social position. As expected, higher mother’s knowledge was significantly associated with lower HbA1C (r = −0.2861705, p = 0.0442). Also, a significant correlation was found between the families’ SES and HbA1C levels (r = 0.4401921; p = 0.0015). Mothers with more knowledge have children with better metabolic control, and low SES is significantly associated with higher levels of HbA1c. Improvement of mothers’ knowledge and family SES may improve glycemic control and ultimately decrease acute and chronic complications of diabetes in children.