Osteoporosis is a disorder characterized by reduced bone mass, impaired bone quality and a liability to fracture. As osteoporosis is a major public health problem with serious medical and economic impact, there have been many advances in the management of osteoporosis over the past 10 years, but important care gaps still exist. It is well established that GCs can influence bone remodeling in a number of ways and at any stage of the remodeling cycle. In general, the pharmacological agents that have undergone assessment for the prevention and treatment of glucocorticoid-induced osteoporosis are similar to those used for postmenopausal osteoporosis.The use of strontium (Sr) for improved bone mineral strength in both animals and humans has been known for almost 50 years, the confusion between normal stable strontium with its radioactive isotopes has led many to shy away from using it. It was stated that its antiosteoporotic effect is accomplished through a unique effect among other antiosteoporotic drugs which increase bone formation as well as bone resorption; as protelos increases bone formation while it decreases bone resorption; therefore restoring bone turnover rate in favour of formation of new strong bone , that provides an early and sustained antifracture effect.In the current study, we investigated the effect of strontium ranelate (protelos) on corticosteroids – induced osteoporosis in rats as an animal model; whether it has any prophylactic effect on bone by delaying the onset or reducing the degree of osteoporosis developed or curative effect by reversing or reducing corticosteroids- induced osteoporotic changes in such model.Hence, adults healthy albino rats of either sex, were divided into three groups: the control group including either untreated or protelos treated rats for 3 months, the disease model group administered hydrocortisone sodium succinate for 3 months and the glucocorticoid-induced osteoporosis treated with protelos either as prophylaxis taking hydrocortisone sodium succinate with protelos simultaneously or therapeutic taking protelos 1 week after the start of hydrocortisone sodium succinate injections.Bone - whether normal or osteoporotic- was assessed using biochemical markers of bone formation (serum total alkaline phosphatase), bone resorption (serum acid phosphatase), osteoblastic activity (serum osteocalcin), serum calcium, serum phosphorus together with histopathologic examination and bone imaging analysis to detect effects of strontium ranelate whether prophylactic and/or therapeutic in the glucocorticoid-induced osteoporosis model.Hydrocortisone sodium succinate induced osteoporotic changes that were progressive along the 3-month study period. SR did not delay the onset of osteoporosis, while it partially and transiently reduced the osteoporosis severity, this effect was of delayed onset and was not sustained till the end of the study. As a therapeutic option, SR reversed partially the corticosteroids- induced osteoporotic and despite an early onset improvement, it was short-lived lasting for only 1 month. As a bone building agent, protelos, alone in normal rats, showed progrssing effect for the first 2 months; which begins to decline by the end of the 3rd and last month of the study.