Diabetes self-management (DSM) practices are an important determinant of health-related outcomes, including health-related quality of life (HRQOL). The purpose of this study is to explore DSM practices and their relationship with the HRQOL of patients with type 2 diabetes in primary health care centers (PHCCs) in Qatar. In this cross-sectional study, data were collected from PHCC patients with diabetes via interview-administered questionnaires by utilizing two instruments: the DSM questionnaire (DSMQ) and the HRQOL Short Form (SF-12). Frequencies were calculated for categorical variables and medians were calculated for continuous variables that were not normally distributed. A statistical comparison between groups was conducted using chi-square for categorical data. Binary logistic regression was utilized to examine the relationship between the significant independent factors and the dependent variables. A total of 105 patients completed the questionnaire, 51.4% of whom were male. Approximately half of the participants (48.6%) reported poor overall DSM practices, and 50.5% reported poor physical health quality of life (PC) and mental health quality of life (MC). Female participants showed significantly higher odds of reporting poor DSM than male participants (OR, 4.77; 95% CI, 1.92–11.86; p = 0.001). Participants with a secondary education (OR, 0.18; 95% CI, 0.04–0.81; p = 0.025) and university education (OR, 0.18; 95% CI, 0.04–0.84; p = 0.029) showed significantly lower odds of reporting poor DSM than participants with no/primary education. Older participants showed higher odds of reporting poor PC than younger participants (OR 11.04, 95% CI, 1.47–82.76 and OR 8.32; 95% CI, 1.10–62.86, respectively). Females also had higher odds for poor PC than males (OR 7.08; 95% CI, 2.21–22.67), while participants with a secondary (OR, 0.13; 95% CI, 0.03–0.62; p = 0.010) and university education (OR, 0.11; 95% CI, 0.02–0.57; p = 0.008) showed significantly lower odds of reporting poor MC. In conclusion, patients with diabetes reported poor overall DSM practices and poor HRQOL. Our findings suggest intensifying efforts to deliver culturally appropriate DSM education to patients and to empower patients to take charge of their health.