Abstract Background and Aims Chronic kidney disease is now recognized as major causes of death in India. The Global Burden of Disease (GBD) study 2015, ranked chronic kidney disease as 17th among the causes of deaths globally (age standardized annual death rate of 19·2 deaths per 100 000 population). Deaths due to renal failure constituted 2·9% of all deaths in 2010–13 among 15–69 year-olds, an increase of 50% from 2001–03. These are varies metabolic derangements in CKD patients, among which volume overload is the major problem contributing uncontrolled hypertension and increases cardiovascular mortality. There will be increased total body water (TBW) and extracellular water (ECW) at the expense of reduced intracellular water (ICW). Renal replacement therapies such as dialysis or kidney transplantation are the major treatment modalities. Renal transplantation is the treatment of choice for end stage renal failure patients. Despite improving renal dysfunction, patients are at risk for existing or new onset of conditions after transplantation and may alter the body fluid physiology. Till date, renal transplant patients received little attention towards fluid balance and nutritional status. There are many studies supporting the use of bioimpedance analyzer as a reliable tool in assessing the fluid status in haemodialysis patients, but there are very few studies done in post renal transplant patients to know their fluid status with single functioning kidney where Glomerular filtration rate are generally much lower than normal. Method fifty renal transplant recipients were followed in our centre for 6 months (68 males, maximum were in 31-45years of age). Biochemical parameters like haemoglobin, urea, creatinine, electrolytes, albumin, estimated glomerular filtration rate (eGFR); TBW, ECW, ICW and over hydration (OH) measured using bioimpedance analysis (BCM, Fresenius) were evaluated at baseline (pre-transplant) and after transplant at 3 and 6 months. Baseline biochemical and bio-impedance values were compared with 3 and 6 months post transplant. Patients were divided into 3 sub-groups based on eGFR: good graft function (eGFR >60 ml/min), borderline graft function (eGFR 30-60 ml/min) and severe graft dysfunction (eGFR >30 ml/min/1.73m2). TBW, ECW, OH and ICW were compared between the sub groups of eGFR at 3 and 6 months post transplant. Results Comparing before transplant with 3 and 6 months post-transplant, TBW, ECW and OH were reduced while ICW increased significantly with good graft function. On comparing 3 months to 6 months post-transplant, ECW, TBW, OH reduced further but there was not much difference in ICW. OH at 6 months post-transplant was 0.6 L (within normal range of gender-matched individuals from the reference population, that is, −1.1 to 1.1 L). In patients with severe graft dysfunction (<30ml/min), TBW, ECW and OH were remained high when compared to borderline (31-60ml/min) and with good graft function group (>60ml/min). Biochemical improvement was comparable with bio-impedance parameters at 3 months and 6 months post transplant with good graft function. Conclusion The BIA showed significant reduction in TBW, ECW and OH by 6 months post transplant and ICW increased as graft function improved post transplantation by 3 months and thereafter, change was not significant. Parameters of Bio-impedance analyzer of well-functioning kidney transplant recipients showed that the altered body water compartments quickly normalizes which is never achieved by a hemodialysis session. We found that Bio-impedance analyzer was useful to know the changes in body fluid composition in post renal transplant patients.