The results of the work aimed at further improvement of the central washing of the rolling drilling tool are presented. The interdependencies of the main factors affecting the efficiency of the cleaning process of drill bit cutting structures and wells bottom zones have been established when drilling with a roller drill tool. The options for the most effective direction of the central jet ting for drill-pipe cutting structures’ various types and design as well as drilling conditions are analyzed. The necessity of carrying out design measures to reduce the adverse effect of the packing formation effect on the peripheral rims of a roller drilling tool equipped by only a central flushing system is substantiated. The advantages and disadvantages of the central scheme of a roller drilling tool washing and various directions of its further improvement are described. New variants of roller drilling tool designs with a central washing circuit, equipped by mobile jetting units are presented. The use of new variants of central hydraulic assemblies constructions that provide better cleaning of the inter-cutter and teeth row grooves of the drill-bit cutting structures of the main and peripheral rims of a rolling cutter as well as the entire well bottom zone as a whole, will make it possible to increase the efficiency of the rolling-cutter drill bits and to reduce the cost of drilling.