An ink tank has a first containing chamber for containing a negative pressure generating member for retaining liquid and being provided with a atmospheric communication hole to make the negative pressure generating member to be communicative with the air outside; and a second containing chamber communicated with the first containing chamber for retaining liquid directly. For this ink tank, a liquid supply port for supplying liquid to the outside is provided for the first containing chamber, and for the second containing chamber as well. With the structure thus arranged, it becomes possible not only to continue stable consumption of ink in the second containing chamber, but even after ink in the second containing chamber is no longer available, ink in the first containing chamber can be used up to the last. Hence, a highly reliable and stable supply of ink is possible even when the number of nozzles or the driving frequency is increased for printing at higher speed.