To realize a water dispersion type pressure-sensitive adhesive applicable in an aqueous system and to provide a removable water dispersion type acrylic pressure-sensitive adhesive sheet especially suitable for the pressure-sensitive adhesive sheet for working a semiconductor wafer, and which causes little stain on an adherend surface and has high resistance to water immersion at the time of grinding the wafer.

The removable, water dispersion type acrylic pressure-sensitive adhesive sheet which is provided on a substrate with a pressure-sensitive adhesive layer formed of the principal component of an acrylic emulsion polymer and which is removable after the application on an adherend, is characterized in that the removable water dispersion type acrylic pressure-sensitive adhesive sheet has, at a tensile test of the above pressure-sensitive adhesive layer, an initial elastic modulus of 0.20-1.5 MPa, the maximum strength of 2.0-8.0 MPa, a breaking extension of 180-900%, and a gel fraction in the pressure-sensitive adhesive layer of 90% or more.

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