The present invention provides an aqueous emulsion excellent in heat resistance, water resistance (particularly, hot water resistance and boiling resistance), and viscosity stability. The present invention also provides an adhesive containing the aqueous emulsion, forming an adhesive layer resistant to staining, and ensuring a high level of safety. The present invention relates to an aqueous emulsion containing an ethylenically unsaturated monomer unit-containing polymer (A) as a dispersoid and vinyl alcohol polymer (B) as a dispersant, wherein, the ethylenically unsaturated monomer unit-containing polymer (A) includes a structural unit derived from a radical-polymerizable ethylenically unsaturated monomer (a) having a functional group represented by the following general formula (W), and the degree of saponification of the vinyl alcohol polymer (B) is 80 mol % or more: wherein, X is an oxygen atom or sulfur atom, and * represents a bond.