The present invention relates to a gas-liquid separator, including a body enclosing a cavity; a gas outlet attached to the top of the body and communicated with the cavity; a liquid outlet attached to the bottom of the body and communicated with the cavity; and an input tube constructed to include a curve shape extending outside the body and communicated into the cavity from the external of the body. The gas-liquid separator of the present invention has got the advantages of a simple structure, easy manufacturing, convenient mounting, and the like, and can separate a gas-liquid two-phase mixture efficiently, thus providing a purer gas flow and a purer liquid flow for downstream processing apparatuses and improving the overall efficiency of the system.