Mechanical fluid pressure type drilling jar of two effects relates to oil machinery, includes moment of torsion transmission mechanism, hydraulic pressure delay mechanism, mechanical locking mechanism, strikes mechanism and sealing mechanism from top to bottom, and hydraulic pressure delay mechanism is equipped with and is used for delayed valve body assembly (1), the lower extreme of bumper jar is equipped with balanced floating piston sealed (2) between urceolus and mandrel, the below of valve body assembly (1) is equipped with the cavity of distribution floating piston (3) between with urceolus and mandrel separates, can be with pressure along the upwards transmission of the cavity between urceolus and the mandrel that balances floating piston (2) below well liquid through balanced floating piston (2) and distribution floating piston (3), and hit the oil pocket under the messenger and be full of oil. It has easy operation, rational in infrastructure, safe and reliable's advantage, can not take place the mistake and shake the phenomenon, can be at any time at the drilling site dynamic adjustment release force, convenient to use, the lubricated environment of totally enclosed, oil bath is favorable to reducing wear, improves instrument life.