Objective: The aim of the work is to study the relationship between Red blood cell osmotic fragility and level of parathyroid hormone in patients with different stages of Chronic Kidney Disease including End Stage Renal Disease. Background: Anaemia is one of the common complications associated with Chronic Kidney Disease (CKD) responsible for the increase in the morbidity and mortality in such patients. Several factors have been attributed to causing renal anaemia, amongst which hyperparathyroidism is one of the less recognised reasons. The level of PTH in early stages of chronic kidney disease has not been much studied. The excess amount of Parathyroid Hormone (PTH) secondary to CKD has been suggested to be a causative factor for anaemia. Method: A number of chronic kidney disease patients were studied for the relationship between Red cell osmotic fragility and level of parathyroid hormone. Results: This study was conducted on a number of 111 patients with chronic kidney disease classified into three groups. The study revealed a significant fall in Hb%, along with a rise in Median Osmotic Fragility (MOF) and PTH in the CKD patients. iPTH and MOF were significantly lower in group 3 as compared with cases in group 1. Also, iPTH and MOF were significantly lower in cases in group 2 as compared with cases in group 1. Conclusions: Based on our findings, secondary hyperparathyroidism has considerable effects on erythrocyte survival, contributing to increased fragility and anemia.