The efficacy and tolerability of once weekly dulaglutide 0.75 mg in Japanese patients with type 2 diabetes (T2D) were evaluated by subgroups defined by key demographic characteristics. This post hoc analysis included data from patients who received dulaglutide 0.75 mg for up to 26 weeks in three phase 3 trials (one open-label, randomized; one double-blind and open-label, randomized; one open-label, nonrandomized). Patients were classified into subgroups on the basis of sex (male, female), age (<65, ≥65 years), body weight (<70, ≥70 kg), body mass index (BMI; <25, ≥25 kg/m²), duration of diabetes (<7, ≥7 years), HbA1c (≤8.5, >8.5%), use of concomitant sulfonylurea (yes, no), and use of concomitant biguanide (yes, no). Efficacy measures analyzed were changes from baseline in HbA1c and body weight and percentages of patients achieving HbA1c <7.0%. Safety measures analyzed were incidence of hypoglycemia and nausea and change from baseline in seated pulse rate. A total of 855 patients were analyzed. Once weekly dulaglutide 0.75 mg improved blood glucose control as measured by HbA1c regardless of patient characteristics; patients with higher baseline HbA1c values had greater improvements compared to patients with lower baseline values. Weight loss was greater in patients with lower baseline HbA1c and in patients taking concomitant biguanides. Concomitant use of sulfonylureas had the greatest effect on the incidence of hypoglycemia. Treatment of T2D with once weekly dulaglutide 0.75 mg for 26 weeks was associated with significant improvement in glycemic control irrespective of age, sex, duration of diabetes, body weight, BMI, or concomitant medication.