Sunflower is an oil-producing plant with a high sensitivity to the attack of various pathogens, due to which is observed a systematic reduction in productivity. The spread and intensification of sunflower crop through all over the world has been accompanied by increased frequency and aggressiveness of pathogens. The most devastating diseases caused by the attack of phytopathogenic fungi are: Plasmopara helianthi (downy mildew), Sclerotinia sclerotiarum (white rot), Botrytis cinerea (gray rot), Phomopsis helianthi (Phomopsis brown stem canker) and Orobanche cumana Wales (parasitic phanerogam-broomrape). In the laboratory of Breeding and growing technologies of sunflower at the RIFC “Selectia” the pathogen attack in the inbred lines nursery (more than 4000 samples) and orientation fields of experimental hybrids (over 300 hybrid combinations) are investigated annually. Testing on resistance to diseases attacking stems is performed according to the method described by T.Selivanov and V.Zateamin (1996). The intensity of the pseudanthium damage by pathogens is appreciated by the method developed by M.Vronschih (1984) for recording the attack level of sunflower with white and gray rot. Evaluation of broomrape resistance is performed under the greenhouse conditions described by A.Pancenco (1975). In the laboratory was appreciated the resistance to downy mildew with express-method elaborated by M.Moldovanu and V.Jivilo (1965). In the field, the pathogens development and disease attack is a process that occurs under the influence of pedoclimatic conditions, which in recent years, due to low humidity and high temperatures (in May-July), 70% of the investigated material showed resistance to Plasmopara helianthi. The development of Phoma black stem and Phomopsis brown stem canker according to line and genotype consisted of 0-40% for Phoma and 0-30% for the Phomopsis brown stem canker. Researches to assess the resistance to broomrape are carried out under greenhouse conditions. Around 300 samples of lines and hybrid combinations are tested annually. Broomrape seeds were collected from different regions of the Republic of Moldova. As witness, were used lines and commercial hybrids that possess resistance genes Or5, Or6, Or7. Resistant were found to be hybrids as Ortac, HS-0428, Basm, HS-1014, HS-1017 and other combinations, as well as 17 lines Rf 37% in total, 15% showed tolerance. Currently, 6 hybrids created at the RIFC “Selectia” are registered in the Catalog of the State Commission for Plant Varieties of Republic of Moldova. In 2017, the hybrid HS-1014 exceeded the witness by 6.5%, harvest consisted 3580 kg/ha of seeds and 1295 kg/ha of oil, and showed resistance to broomrape. This hybrid has been recommended by the State Commission as a perspective hybrid for 2018.