The present invention provides a water-based skin cosmetic comprising the following ingredients (A) and (B): (A) A compound represented by the following formula (I) (In this formula, l and m can be either the same or different; each denotes an integer 10-25.) (B) A thickener composed of microgel obtained by using a composition that has an organic solvent or oil component as the dispersion medium and water as the dispersion phase, dissolving a water soluble ethylenically unsaturated monomer in the dispersion phase, and radically polymerizing it in the dispersion phase, wherein said microgel is obtained by radically polymerizing dimethylacrylamide and 2-acrylamido-2 methylpropane sulfonic acid under the conditions in which a single phase microemulsion or fine W/O emulsion is formed by using a surfactant.