Aim: The aim of this study was to assess thyroid hormone levels in among diabetics in Port- Harcourt of Rivers State in Nigeria Study Design: This study is a cross-sectional study. Place and Duration of Study: This study was conducted at Chemical Pathology Department, Rivers State University Teaching Hospital, Port Harcourt, Nigeria, between December, 2019 and February, 2020. Methodology: A total of 224 subjects were recruited for the study, diabetic parents (132 subjects), non-diabetic parents (112 subjects. Five (5) ml of blood sample was collected and used to analyse for serum thyroxine (T4), tri-iodothyronine (T3) and thyroid stimulating hormone (TSH) using Enzyme-linked immunoasorbent assay. Data were analyzed statistically with SPSS version 22.0 and values considered significant at p< 0.05. Results: The mean ± S.D of serum TSH were 1.28± 0.6u/ml (control) and 1.84±1.05 u/ml (subject), (p=0.023). T4 value were 2.49 ± 0.86u/ml (control) (p=0.024) and 3.90 ±1,62u/ml (subjects) and T3 values were 1.89±0.41u/ml (p=0.0001). Conclusion: The evaluation of thyroid hormones (TSH, T4 and T3) among diabetes with the age ranges of population studied shows that there was altered thyroid hormone in diabetes mellitus individuals.