Abstract: This was the first paper of the thematic lecture for ordinary downhole control tools and their design of horizontal well. At the beginning, it introduced the definition and classification, as well as the technology characteristics of long, middle and short radius horizontal wells; On the basis of this, it further introduced the classification, classification method and structural features of various ordinary tools for long and short radius horizontal wells; For short radius horizontal wells, ordinary tools and structural characteristics were introduced according to the detailed classification of medium-short, general short and extra-short radius, The structural form and important technical parameters of some typical tools were illustrated with diagram and table.