Ideal packing technology was a new reservoir protecting technology, which was based on d₉₀ (particle diameter with accumulation of 90% volume fraction on the size composition of accumulated distribution curve) rule. By considering the whole formation pore throat size, temporary plugging agent with suitable particle size could be optimized by this technology and achieve better reservoir protecting effect. Based on the characteristic of reservoirs of major blocks in Tuha oilfield, the ideal packing technology was applied to optimize temporary plugging projects of twelve blocks for protecting the reservoirs, including Qiuling, Wenmi, Shanshan and so on. Using a self-developed ideal packing temporary blocking software, a combination of three temporary plugging agents with 1000, 600 and 100 mesh in mass ratio 2:13:5 could make d₉₀ of the particle in drilling fluid (110.92 μm) larger than the maximum pore size of reservoir (d_max=80.33 μm), which could effectively plug pore throat with various sizes in reservoir. The experiment results showed that the optimized temporary plugging agent could improve the buildup of core permeability and reduce the filter loss without impacting the rheology of the drilling fluids. The appropriate amount of the compound temporary plugging agents was 3%. The reservoir permeability recovery value improved from 30% to more than 80%, which had a good reservoir protection effect. This technology was applied in 20 wells in Tuha oilfield, as a result, the daily fluid production of testing wells increased more than 45% than that of adjacent wells, and the average water content was 18%.