Provided is a cooker with a steam generating function without leakage of water and having excellent reliability and durability. A connecting member is formed of a soft material, and is guided by a convex-shaped guide portion 1 having a rounded tip when it is inserted into an opening concave portion 8 of a water tank 6 (Fig. 4), and a convex-shaped seal portion 2 for ensuring a seal can uniformly contact the opening concave portion 8. Moreover, the convex-shaped seal portion 2 for ensuring the seal is integrally formed with a connection portion 3. Therefore, the durability and the reliability for slipping-off prevention can be enhanced, and the number of components can also be reduced.
