Absorbent article

An absorbent article comprising a main body including:

• a liquid-permeable surface sheet;
• a back sheet-;
• and an absorbent core sandwiched between said surface sheet and said back sheet, and two leakage preventing walls extending in the longitudinal direction of said main body and provided on two sides of said main body lying opposite one another in the widthwise direction thereof,
• the overlap of said absorbent core and said surface sheet including:
• a main absorbent portion located between said two leakage preventing walls and at the center of said overlap in the widthwise direction;
• and two grooved portions formed by depressing said overlap and each located between said main absorbent portion and corresponding one of said two leakage preventing walls,
• wherein the fiber density of the portion of said surface sheet forming said main absorbent portion, the fiber density of the portion of said surface sheet forming said grooved portion and the fiber density of said leakage preventing wall are related in the order of said grooved portion>said leakage preventing wall>said main absorbent portion.