In the Republic of Moldova sunflower crops by the content of oil occupies the first place. According to some studies in order to obtain a high potential productivity of sunflower plants is used not only adaptive ecological properties varieties they possess but also biologically active substances. In this perspective the biologically active substances are produced by the algae. Utilization of bioproducts as bio-stimulators are welcome, especially since they are environmentally safe. This study aimed the influence of ES {extract from Spirulina platensis} on metabolic processes occurring during plant growth and development of sunflower. The experiments were carried out both in laboratory and field conditions. Biopreparate ES was used in the following concentrations: 1%; 0.5%; 0.25%; 0.125%. Sunflower seeds were treated with ES for 6 hours by soaking. As the witness served the distilled water. During the growth and development of sunflower plants were studied: energy and seed germination capacity; plant growth index, enzymatic activity, photosynthetic activity, harvest and productivity indices. The results obtained showed that the highest degree of stimulatory effect on germination of seeds had concentrations of 0.25-0.5%. These concentrations occur increasing germination capacity, plant growth index, increases activity enzyme in germinated seeds. Was highlighted the degree of influence of ES biopreparate in photosynthesis: increases the foliar surface (by 7%), the photosynthetic potential (by 37.8%) increases the accumulation dried biomass (by 16.7%) compared to the control. At the same time the influence of the biopreparate ES is it also manifests in the case of the accumulation of assimilating pigments in the sunflower leaves, especially in the phase preceding the fructification - by 37.1- 41.5% more than the control. Biopreparate ES has a beneficial effect on its crop and its quality. Increases the number of seeds (21.3%), seed mass (by 25.2%), oil content (by 4.5%), compared to the witness. There is an improvement in the quality of the sunflower oil expressed by modifying the sum of the amino acids, on account of the essential ones (valine, lysine, arginine).