Nowadays, sunflower (Helianthus annuus L.) is one of the most widely cultivated oil crop with significant impact for rational side of human nutrition (Robinson, 1975). In connection with production process of sunflower Brandt et al. (2003) stated that forming of achene yield and quality is a complex process, conditional by function and frequency of many factors, which in their interactions make complex structure of growth, physiological and biochemical processes. Considering the environmental and health problems arising from chemical fertilizers usage, much attention has been drawn to the application of biological fertilizers in agriculture. Fertilizers administration can increase sunflower growth and yield substantially (Cechin, 2004). Generally, the biostimulants are the organic substances used in low concentrations, involved in physiological processes of growth and plant development, which produce favorable effects, both quantitative and qualitative on crops while reducing losses due to transport and storage products (Anton, 1995). Growth and development of sunflower are a combination of many events at many different levels, from biophysical and biochemical to tissue and organ levels. The biostimulants and their combinations significantly affect growth analysis and some growth attributes and some agronomic characters as well as yield and its components (Bakht, 2010). Considering the economic importance and yield potential of the crop, this study was conducted to investigate the effect of biostimulant ”Fertileader Gold” application on growth indices of Helianthus annuus L. under field conditions. The investigations were carried in experimental field of Institute of Genetics and Plant Physiology, which was prepared for the ”International Symposium on Broomrape (Orobanche spp.) in Sunflower”, Chisinau, Republic of Moldova, August 25-27, 2011. Seeds of sunflower of 15 commercial hybrids (Sandrina, ITC-06, ITC-09, Procera 2, Super 5, Super 3, Super 1, Performer, Sensibil 1, Novi Sad 1, Novi Sad 2, Novi Sad 3, Limagrain 3, Limagrain 4, Limagrain 5) were obtained from National Agricultural Research and Development Institute, Fundulea, Romania and other European Sunflower Seed Producers. In order to rich our aim, the biofertilizer applied was ”Fertileader Gold” (1%), produced by S.C. Timac AGRO România S.R.L. It is a foliar biostimulant which is a complex of specially selected and extracted natural plant phytohormones, macro- and microelements used to boost the potential of normal plant physiological processes, like root development, photosynthesis and mineral movement within the plant. It was directly sprayed on the field. The plants were harvested at maturity and traits such as plant height and head diameter were recorded on 80 randomly selected plants in each plot. Control plants were grown without biofertilizer application. The application of biostimulant was found to be beneficial for the growth of sunflower seedlings. Data analysis showed that the morphological and growth traits including plant height and head diameter was positively affected by organic fertilization. The highest plant height (206,55 cm) were observed at hybrid Sensibil 1, and the minimum plant height recorded in control was attested at sunflower genotype Sandrina (142,48 cm). Application of ”Fertileader Gold”, increased the plant height by 12,65% (ITC-06), compared to control. These results are in line with the findings of other researchers (Aowad and Mohamed, 2009). Another growth trait was the head diameter, which contributes considerable share in final achene yield as it influences both the number and weight of achenes. The head diameters of sunflower plants varied with each genotype and these differences were found to be significant. Moreover, the maximum values of head diameter (29,29 cm), was recorded at genotype Novi Sad 3. The minimum head diameter was noticed in control at hybrid Limagrain 3 (19,93 cm). The plants that were treated with this biostimulant showed about 22,35 % more head diameter (Novi Sad 3), than nontreated plants. The results for head diameter were in concordance with results obtained by Asad et al. (2003). Also, simple correlation analysis between percent of effect of biostimulant on sunflower plant height and its influence on head diameter indicated a negative significant correlation (r = - 0,6662) between mentioned traits. This information may be useful for selecting higher yielding varieties for sunflower production. Results obtained from this study clearly indicated that biostimulant treatment had significant effects on growth stages of sunflower. Its application represents an important measure to correct nutrient deficiencies and to replace elements removed in the products harvested, and has been shown to be particularly effective with respect to yield formation.