The trend for development and spreading of diseases and pests of blackcurrant at Orel region in the conditions of extreme drought in 2010 has been detected. Abnormal weather conditions of the summer and the lack of precipitation limited both growth of host plant and disease spreading. At the background of extreme conditions of 2010 the crop phenophases shifted to earlier dates. The awakening of wintering pathogen structures began in the classic dates of the spring, although in summer their biological cycle went off rapidly. Due to the lack of moisture the disease pathogens failed to fully realize their potential of development and spreading. A favorable aspect of the extreme conditions of vegetation period, the reducing of the protective measures against diseases, is to be admitted. Abnormal weather conditions accelerated the pathogen biological cycles and reduced the stock of wintering infection; meanwhile they provoked colonization of the plants by pests. In extremely high air temperature and lasting lack of precipitation the pests number was intensively increasing, exceeding the maliciousness threshold. Due to the above some additional insecticide and acaricide treatments of berry crops were applied. Thus, the vegetation period of 2010 was described as most favorable for the development and spreading of pests and less favorable for disease pathogens.