The invention relates to a push-the-bit fully-rotary guiding tool. The push-the-bit fully-rotary guiding tool comprises a centralizer mechanism, a guiding actuating mechanism and a spline cardan shaft mechanism. The front end of the guiding actuating mechanism is connected with the spline cardan shaft mechanism; the rear end of the guiding actuating mechanism is connected with the centralizer mechanism; and when the rotary guiding tool conducts guiding drilling, a controlling system controls a down-hole motor to enable a specific hole in a big gear to communicate with drilling liquid channels in an upper main body and a lower main body of the guiding mechanism at a specific position so as to adjust an irrotational shell to the position where a needed guiding well deflection and a needed guiding direction are the same, then a drilling tool conducts drilling along the needed well deflection and the needed direction, and a well track is monitored by all while-drilling testing instruments at any time. The push-the-bit fully-rotary guiding tool has the characteristics that the build-up rate is high, application range is wide, and the obtained well track is high in quality.