A multilayer absorbent core for use in disposable absorbent articles, and manufacturing method thereof； the absorbent core is formed by compacting respective layers； the surface of the absorbent core has grid grooves, and the groove depth at the cross points of the grid grooves is greater than the groove depth at non-cross points. A novel synchronous staggered-layer compacting process is employed, that is, a linear reticular trapezoid compacting mechanism (1) having the height lower than a cone structure (2) partially compacts the absorbent core while the cone structure (2) compacts the absorbent core in a dotted manner, and the absorbent core is divided into a plurality of small protruding spaces to completely restrict the migration of polymer absorbent material in the absorbent core while maintaining the drainage function of a flow directing layer and a liquid storage layer, as well as increasing the strength of the core. The present invention adjusts the structure and manufacturing process of the core, allowing the improved multilayer-structure absorbent core to have greater liquid absorption, higher liquid absorption speed and increased strength.
