Tugai forests are intrazonal forests formations, which grow along bottomlands of rivers in arid regions. These forests are called intrazonal forests because they are not separate zones. They are like inclusions in an extensive arid zone but they are intra-area vegetation, which is different from the main background arid flora. Main tree species are Populus diversifolia Schrenk, Populus pruinosa Schrenk, Fraxinus sogdiana Bunge and Elaeagnus angustifolia L. Area of the tugai forests is decreasing because of many reasons. The aim of this study was to know some reasons of their degradation. There were used methods of forest pathology observation. We installed window traps for catching insects, which are pests. In addition, we collected samples of damaged parts of trees as herbarium to know diseases. According the results of this study, the main pests and disease of tugais were identified. Description of main pests was written. The most numbered species of pests was Hylesinus varius Fabricius for Fraxinus sogdiana. Scolytus jaroschewskii Schevyrew was often in Elaeagnus angustifolia. Agrilus ganglbaueri Semenov was identified for both species of Populus. The main disease of Populus pruinosa was Melampsora tremulae Tul. Melampsora populnea Pers. P. Karst. For Fraxinus sogdiana and Elaeagnus angustifolia dangerous diseases were not established. For conservation of the tugai forests, ecosystem method of study and forest pathology monitoring will be suggested