34 female, 7-week-old, Sprague-Dawley rats were used to investigate the effect of high-fat diet on postmenopausal osteoporosis. 26 of them were subjected to bilateral oophorectomy. 13 of these were then fed on a high fat diet (group A), the other 13 were fed a normal, regular diet (group B). Eight untreated rats were fed on a normal, regular diet and Selved as controls. Five months after their oophorectomy, the hypercalorific diet was found to have diminished the calcium content of lumbar vertebrae (L3, L4 and L5). This study shows that rats fed on a high-fat diet did reduce their food intake and food conversion efficiency. Therefore, this diet induces generalised malnutrition and thus contributes to the proccess of osteoporosis. Oophorectomy induces endocnnological changes that contribute to the development of osteoporosis. This work leads us to conclude that the oophorectomised rat provides a good experimental model for the study of postmenopausal osteoporosis.