Sclerotinia sclerotiorum (Lib.) de Bary is one of the major diseases of sunflower (Helianthus annuus). The pathogen can attack all parts of the plant at every stage of plant growth, predominantly the capitulum, leaf and stem. In the present study, several perennial Helianthus species of diverse origin were evaluated for resistance level to mid-stem and leaf infection using an inoculation method. The evaluation revealed considerable and significant differences among the genotypes in all recorded resistance traits. Three genotypes showed enhanced resistance levels to mid-stem reaction. Two genotypes exhibit resistances to leaf infection. Since all evaluated resistant genotypes in these trials are sexually incompatible with the Helianthus annuus genome, newly developed biotechnological methods gain particular importance for the transfer of the discovered levels of resistance into the cultivated sunflower.