Model ZDQ hydroscillator improves the effectiveness of bit pressure transmission and frictional resistance between BHA (the pit bottom assembly like drill bit, centering guide, extra-heavy drill rod ( drilling tools) except for ordinary drilling rod in drilling process by the longitudinal vibration generated by itself, especially to improve the drilling pressure transmission with a screw, reduce the frictional resistance, cut down the ordinary drilling sticking accidents, increase the dynamic drilling pressure and improve drilling efficiency in directional drilling process.