A piston for a compressor is disclosed. The piston for the compressor compressing and discharging a refrigerant sucked into a cylinder includes a sliding portion disposed in the cylinder and having a suction space to receive the sucked refrigerant, a head portion coupled to the sliding portion, a compression space being formed at a front of the head portion and the suction space being formed at a rear of the head portion, the head portion comprising a suction port communicating the suction space with the compression space, a press-fit cap coupled to the front of the head portion, the press-fit cap comprising a suction hole connected to the suction port, and a first elastic member disposed between the press-fit cap and the head portion. A gas layer is formed between the head portion, the press-fit cap, and the first elastic member.