Hemodialysis therapy is the core of treatment for patients with chronic kidney disease (CKD). The degree of compliance to the therapy, diet, and fluid restrictions determines the quality of life of hemodialysis patients. The present study aims to determine the therapeutic compliance and functional capacity of patients undergoing hemodialysis. Objective: The objective of this study is to determine the therapeutic compliance and functional capacity of patients undergoing hemodialysis. Methodology: A cross-sectional descriptive research was conducted among 50 hemodialysis patients at a selected tertiary care center, Chennai. After obtaining the setting permission and informed consent from participants, data was collected using pretested and validated tools such as background variables proforma of adults such as gender, religion, marital status, occupation, monthly income, educational status, type of family and health insurance, and clinical variables of adults such as height, weight, BMI, BP, potassium, urea, creatinine. Functional independence measure for the assessment of functional capacity, and rating scale for the assessment of therapeutic compliance. Data was collected by a self-administration method using the questionnaire method. The main data collection was done after determining feasibility and practicability by a pilot study. The data was tabulated and analyzed by using descriptive and inferential statistics. Results: The study reveals that the mean scores for each component of the therapeutic compliance regarding hemodialysis among hemodialysis patients such as potassium restrictions (4.11 ± 0.994), phosphorus restrictions (3.72 ± 1.17), fluid restrictions (3.78 ± 1.055), attendance in dialysis session (4.12 ± 0.93) with the overall mean scores of therapeutic compliance on hemodialysis as 11.18 ± 4.07. Conclusion: The study aims to determine the relationship between functional capacity and therapeutic regimen compliance in patients undergoing hemodialysis.