The invention relates to the technical field of kitchen utensils for cooking foods in steam and discloses a water-steam separation box for a steam cooker.The water-steam separation box comprises a box body which is provided with a water inlet, a water outlet, a steam outlet and an air inlet pipe, and an outlet of the air inlet pipe is positioned in the upper portion of the box body.By separation of steam and water drops, steam entering a cooker body carries less moisture, steam purity is higher, and heating efficiency is higher; preheating of water can be realized, and preheated water flows back into a steam generator to further increase steam discharging speed; in addition, separation of the steam and the water drops is beneficial to noise reduction, and noise is isolated inside the box body of the water-steam separation box, so that spreading of the noise into the cooker body can be avoided, and a silencing effect is achieved.