Iron deficiency which is a public health problem in many developing countries is not only due to an insufficient supply, but also to a problem of bioavailability of iron in foods. The aim of this study was to determine the optimal conditions (time and temperature) of steam blanching of spinach leaves, and the effect of blanching on its chemical composition and functional properties. To achieve this, spinach was collected in the Ngaoundere main market, fresh and undamaged leaves separated and cleaned. The optimal conditions were determined using the plan of Doehler, where time and temperature of steam blanching varied from 2.5 to 12.5 minutes and 80 to 100°C respectively. Sample obtained was dried at 45°C ± 2°C for 24 hours and crushed to obtain a flour with a diameter of particles ≤ 500 μm. Responses sought were the maximum iron content and the minimum phytate/iron ratio in flour obtained. Chemical composition and functional properties of flour obtained with and without blanching was determined to evaluate the effect of steam blanching on spinach leaves, and data were analyzed using T-test at P<0.05. Results show that the optimal conditions of steam blanching of spinach leaves are 5 min at 95 °C. under these conditions, there was a significant increase (p<0.05) of iron content and a reduction of phytate/Iron ratio. Steam blanching of spinach leaves do not have any effect on carotenoids, magnesium and macronutrients content, but significantly reduces phosphorus content and increases calcium content. There is also a significant (p<0.05) decrease of anti-nutrients content (more than 50%). Water absorption capacity, water solubility index and bulk density are better in flour produced with blanched leaves. These results suggest that flour obtained with spinach leaves after steam blanching at 95°C for 5 min is a good source of bioavailable iron, so it can be used for infant food formulation and fortification.