The invention discloses a cable-piercing hydraulic oscillator. The cable-piercing hydraulic oscillator comprises an upper connector, a
piston, a compression spring, an outer jacket, a lower connector,a first sealing
assembly and a second sealing
assembly, wherein the upper connector and the lower connector are connected through the outer jacket; the outer jacket is arranged on the outer parts ofthe upper connector and the lower connector; the
piston is arranged on the inner part of the outer jacket; a ring-shaped cavity is formed between the outer jacket, the
piston and the lower connector;the compression spring is arranged in the ring-shaped cavity; the first sealing
assembly is arranged between the upper connector and the outer jacket; the second sealing assembly is arranged between the outer jacket and the lower connector; a sealing cavity is formed between the piston and the upper connector; holes are formed in the upper end of the piston; the holes communicate with the sealingcavity; and the piston and the lower connector can move up and down in the cable-piercing hydraulic oscillator under the action of
pressure difference. The cable-piercing hydraulic oscillator has thebeneficial effects that the whole hydraulic oscillator has a good sealing performance, and a flexible vibrating and rectangular limiting connection mode makes the
reciprocating motion continuous well.