A foldable liquid container includes a foldable supporting frame, a foldable container body arranged on the foldable supporting frame, and a switch device arranged on the foldable supporting frame to be operated to transform the foldable supporting frame between an unfolded mode and a folded mode in a single puling operation. The foldable container body is able to be folded with the folding of the foldable supporting frame. The foldable supporting frame is supported and secured in the unfolded mode by means of the switch device, wherein the switch device can be operated to release the engagement of the foldable supporting frame while transforming from the unfolded mode to the folded mode.