The present invention discloses a drilling speed increasing device driven by a downhole motor for generating shock vibration. The device uses the rotational energy of a screw motor as power to drive a lower vibration starter to rotate. Vibration starting steel balls have the function of reducing friction in the interior. During axial reciprocating motion of the upper vibration starter, a spring matched with the upper vibration starter is periodically compressed to generate spring energy. The spring energy reacts on the lower vibration starter and a main shaft connected with a drill bit, so as to periodically provide drilling pressure for the drill bit. Periodic motion of the upper vibration starter and the spring produces periodic axial vibration on the tool.