Abstract: "Wellbore plugging" phenomenon, which always accompanies the whole production cycle, has seriously affected oil and gas production and reservoir exploitation in the Bashituo Oilfield. Colloid instability of internal oil, formation, and pressure drop are the main reasons for asphaltene precipitation and wellbore plugging. By pressure derivation, the predicted depth of asphaltene precipitation ranges from 500 to 2 400 m. Mechanical descaling focused on these sections during production process can successfully help to achieve the purpose of wellbore plugging prevention.