Background: Type 2 diabetes is characterized by hyperglycemia and hyperinsulinemia. Diabetes mellitus is common worldwide because an average adult's bloodstream has 100 milligrams per deciliter of glucose at five to ten grams. Diabetes-related renal and cardiovascular diseases are more expensive and medically burdensome. One common bone disease is osteoporosis, characterized by weakening bones that increase fracture risk, causing discomfort, impaired function, and lower quality of life. Aim: This study aims to evaluate some biochemical variables for diabetic female patients (Calcitonin, Ca, Vitamin D, ALP). Methods: The study included blood samples from 120 women. The samples were classified into two groups, a control group with 40 samples and a group of diabetic patients with 80 samples. The study was conducted at the Endocrinology and Diabetes Center in Maysan Governorate from January 2023 to April 2023. The women’s samples were medically checked by a diabetes specialist and were diagnosed with diabetes, and some of them are obese according to (BMI and HbA1c) levels. Pregnant women and smokers were excluded. The ELISA method using a SUNLONG calcitonin kit was used to determine the serum level of calcitonin; the (Ca, ALP) kits manufactured by A15 BioSystems were used to determine calcium and Alkaline Phosphatase, while Vitamin D used a VIDAS kit. Results: The current findings revealed a significant effect (p<0.05) in all variables in D.M. patients that were detected compared to the control group (The control group was chosen on the basis that individuals are free of diabetes, obesity, and other chronic diseases and within the age group 20-65 years). The results show a significant decrease in Calcitonin and Calcium (p<0.05), and non-significant differences in Vitamin D and ALP (p>0.05) in D.M. patients, which was detected in comparison with the control group concentrations. Discussion: The current study's findings indicate that calcitonin reduces circulating calcium, leading to the theory that its physiological role in hypercalcemia may be involved in returning average serum calcium concentrations. A vitamin D shortage compromises pancreatic beta cells' ability to secrete insulin in response to glucose, pancreatic cells express vitamin D receptors that bind to the active circulating form, 1,25 (O.H.)2D. Conclusions: The study underscores the significant changes in calcitonin and calcium levels in diabetic female patients compared to healthy controls, suggesting the need for careful monitoring of these biochemical variables in diabetes management. The findings offer new insights into the metabolic aspects of diabetes, highlighting potential areas for therapeutic intervention.