The invention relates to the technical field of fuel cells, and discloses a bipolar plate assembly and a fuel cell. The bipolar plate assembly comprises a polar plate body, a wedge-shaped structure and a water guide assembly, wherein a gas flow channel is formed in the polar plate body; the wedge-shaped structure is arranged in the gas flow channel, a first inclined face is arranged on the side, which is away from the bottom of the gas flow channel, of the wedge-shaped structure, the first inclined face inclines upwards in the direction from an inlet of the gas flow channel to an outlet of thegas flow channel, and the water guide assembly is arranged on the wedge-shaped structure and used for guiding out water generated by gas fuel reaction. According to the bipolar plate assembly provided by the invention, the longitudinal sectional area of the side, which is close to the outlet of the gas flow channel, of the gas flow channel is smaller than that of the side, which is close to the inlet of the gas flow channel, of the gas flow channel, the gas flowing speed is increased, and uniform distribution of gas concentration in the whole flow field is guaranteed; and by arranging the water guide assembly, water produced by gas fuel reaction can be discharged in time, and gas transmission is prevented from being affected.