Abstract: The present invention relates to a toilet bowl with a changeable water seal, which comprises an upper region, a waste drain outlet of the upper region, a lower region and a waste drain outlet of the lower region. A deviated waste discharge passage is fixed on a supporting shaft or a supporting bore. A reposition apparatus is arranged for the reposition of the waste discharged passage, the lower end of which surrounds the waste drain outlet of the upper region, the higher end of which could be depressed and repositioned automatically and be lead to the waste drain outlet of the lower region. This invention could overcome these disadvantages that immobile waste discharge passage of the traditional toilet bowl between the waste drain outlet of the upper region and the waste drain outlet of the lower region has a higher water seal, a higher water resistance and higher water consume.