An absorber containing non-wood pulp with the settling velocity in water between 2 and 5 seconds, the mean fiber size of 8 to 25 μm, the apparent bulk density of 0.04 to 0.07 g/cm3, and the absorption for 0.9% physiological saline of at least 20-fold with respect to the pulp mass. The absorber has a thickness change of at least 600%, as the thickness after having absorbed 0.9% physiological saline with respect to the thickness before absorbing 0.9% physiological saline. When addition of 80 mL of 0.9% physiological saline to the absorbent article over a period of 10 seconds is performed three times every 10 minutes and the absorption rate of the absorbent article for each of the three times is evaluated as the time from addition of the 0.9% physiological saline until complete absorption, the absorption rate for each of the three times is not greater than 20 seconds.
