The invention provides a device for producing oxamide by utilizing a high-gravity reactor and a production method thereof. The device includes a dimethyl oxalate storage tank, a methanol storage tank, a liquid ammonia tank and a water tank. The dimethyl oxalate storage tank is connected to a solid inlet of a material burdening kettle through a solid transporter. An outlet of the methanol storage tank is connected to a liquid inlet of the material burdening kettle through a first pump. The outlet of the material burdening kettle is connected to a liquid inlet of the high-gravity reactor through a second pump. The liquid ammonia tank is connected to a gas inlet of the high-gravity reactor through a reducing valve. The outlet of the high-gravity reactor is connected to a solid-liquid separator. The solid outlet of the solid-liquid separator is connected to a dyer. A solid outlet of the dryer is connected to an oxamide finished product storage tank. A gas outlet of the high-gravity reactor and a gas outlet of the dryer are connected to the water tank separately. The device and the method have advantages of continuous production, a small size, low reaction temperature, and a low production cost.