Water-gas separation device and fuel cell system

The invention discloses a water-gas separation device and a fuel cell system, and belongs to the technical field of fuel cells. The water-gas separation device comprises a separator and a pipeline assembly, the separator is provided with a mixed fluid inlet, a gas outlet, a liquid outlet and an exhaust port, the mixed fluid inlet is located on the side wall of the separator, and the gas outlet islocated at the top end of the separator; the liquid outlet is formed in the bottom of the separator, the exhaust port is formed in the top end of the separator, and a first flow collecting channel isfurther formed in the side wall of the separator and extends in the length direction of the separator; the pipeline assembly comprises a first pipeline and a second pipeline which communicate with each other, an included angle is formed between the second pipeline and the first pipeline, and the second pipeline communicates with the mixed fluid inlet; the first flow collecting channel is located on the downstream of the mi