The frequent application of pesticides against Citrus pests and diseases such as leaf-miner (Phyllocuistis citrclla Stainten) . red mite (Pauxychus citri), rust mite (Phyllocotruta vlcivora) and cankes (Xanthomonas citri) has resulted in the resistance to pesticides, environmental pollution, death of the natural enemies and break up of ecological balances. The present study is based on the theory of ecology and the knowledge of the developmental patterns of the pests and diseases. A series of integrated techniques of prevention and control, consisted mainly of advanced cultural practices including removal or cut-back of the summer shoot, stimulation of the autumn flush at planned dates and removal of the diseased leaves before the growing-out of each flush in order to reduce the ground population of pests and the amount of disease organisms, were proposed in combination with the improvement of orchard ecological environment including use of proper weed cover and establishment of windbreaks in the orchards in order to stimulate the multiplication of the natural enemies and to prevent Citrus psylle (Diaphorina citri) dispersion and spread, development of a convenient forecasting method, and determination of population indices and adoption of spring orchard cleaning in stead of winter orchard cleaning for effective spraying. After experimentation at 6 locations with at least 20, 000 hactares of citrus groves from 1978 to 1989, we have gained significant ecological, economical and social benefits. Especially the spraying expenses were reduced by half.