Abstract: This study was conducted with the aim of assessing the effect of plant extract derived from drought stressed rose leaves in controlling black spot disease of roses caused by Diplocarpon rosae infection. The plant extract is shown here to contain elevated levels of various reactive molecules such as H2O2, O2-, nitric oxide (NO), malondialdehyde (MDA) and expression of pathogenesis related proteins mediating defence responses in plants. Treatment of rose plants with the extract promotes black spot disease resistance through enhanced expression of pathogenesis related proteins, peroxidase and accumulation of defence response elicitors. These data suggest that plant extract from drought-stress leaves can be used as a promising alternative to control plant diseases in an environmentally friendly way.