The invention provides a desanding and gas exhausting device, relating to the field of treatment of oil field fracturing fluid returning water. The desanding and gas exhausting device comprises a water inlet, a separation tank and a water outlet, wherein the separation tank consists of a first-stage separation tank and a second-stage separation tank, the water inlet is communicated with the first-stage separation tank by virtue of a pipeline, the inner part of a tank body of the first-stage separation tank is provided with an umbrella-shaped collecting device, the umbrella-shaped collecting device is communicated with the second-stage separation tank water inlet in a tank body of the second-stage separation tank by virtue of a liquid communicating pipeline, the upper parts of the first-stage separation tank and the second-stage separation tank are both provided with gas exhaust openings, and the gas exhaust openings are communicated with a gas treatment device by virtue of a gas communicating pipeline. According to the desanding and gas exhausting device provided by the invention, effective separation of sand, water and gas can be effectively achieved by virtue of two-stage separation, and separated gas is communicated with the gas treatment device by virtue of the gas communicating pipeline, so that the body health of workers can be ensured; and the desanding and gas exhausting device is simple in structure and convenient to manufacture.