Objective: The purpose of this study is to estimate the cost-effectiveness of screening, treatment, and examination of patients with type 2 diabetes during a yearly period and expose its importance in diabetes control. Materials and Methods: Five hundred patients with type 2 diabetes who had received outpatient therapy in the past year were enrolled in the study. Patients were divided into three categories according to their hemoglobin A1c (HbA1c) (%) levels: good control (HbA1c <7%), fair control (HbA1c 7%–10%), and poor control (HbA1c >10%). Average annual costs of treatment, examination, and laboratory workup were compared for the three groups. Results: The average annual cost of medication for 500 type 2 diabetes patients was $556.50, while the cost of screening and examination was $89.20 per patient. The average yearly treatment cost per patient was $287.90 for patients with HbA1c ≤7%, $647.90 for patients with HbA1c 7%–10%, and $752.40 patients with HbA1c ≥10%. The average annual costs of treatment with only oral anti-diabetic drugs (OAD), insulin only, and both OAD and insulin were $154.80, $837.50, and $819.30, respectively. Conclusion: While the cost to treat diabetic patients with good control was significantly lower than the treatment cost of patients with poor control, there was no significant difference in laboratory workup and examination costs. When patients treated with OAD only, insulin only and OAD + insulin were compared, treatment costs for the OAD only group were significantly lower than the costs to treat the insulin only and OAD + insulin groups. No correlation between age or sex and medication cost were found. However, a strong correlation was found between diabetes duration and treatment cost.